Application crash when middle mouse button click on clip in song editor

[zeganstyl]

Bug Summary

When I click with middle mouse button on clip in song editor to remove this clip, it leads to whole application crash sometimes, while song is playing.

Affected LMMS versions

1.3.0-alpha.1.102 (OS Ubuntu 20)

[Monospace-V]

Did you delete a piano roll clip, automation track clip, sample track clip or B/B instance?
Can you give us more information on how to replicate this? Or give us a sample project file and provide instructions on what to do to crash the app?
I cannot replicate this on an empty project, or with a few notes in piano roll.

[zeganstyl]

@Monospace-V, I am using VST plugins through Wine: DrumKit1, TAL NoiseMaker, DSK ChoirZ.
I have 25-30 tracks (Beat+Bassline, no automation clips) in song editor.
Crash can happen in a few minutes or maybe even after half an hour. So it can be difficult to reproduce it.
I remember that it happening only when I delete B/B instance. Other cases were either too rare or the error did not appear.
And it happens only while playing song.

[zonkmachine]

@zeganstyl Can you produce a backtrace of the crash?

[zeganstyl]

@zonkmachine, I will try

[zeganstyl]

Finally, I have catched this bug.

Here I firstly worked with another project (more large, with same plugins + some other) and it worked fine.
Then I switched to project, where were crashes. In this project I have several instances of same plugin: TAL NoiseMaker, but in previous project that plugin was with one instance.

LMMS Debug

Copyright (C) 2020 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
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There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
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For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from squashfs-root/usr/bin/lmms.real...

warning: Loadable section ".dynstr" outside of ELF segments
(gdb) set sysroot ./squasfs-root
(gdb) set solib-search-path ./squashfs-root/usr/lib
(gdb) run
Starting program: ~/apps/squashfs-root/usr/bin/lmms.real 
warning: Unable to find dynamic linker breakpoint function.
GDB will be unable to debug shared library initializers
and track explicitly loaded dynamic code.
warning: Could not load shared library symbols for 21 libraries, e.g. /lib/x86_64-linux-gnu/libpthread.so.0.
Use the "info sharedlibrary" command to see the complete listing.
Do you need "set solib-search-path" or "set sysroot"?
[New LWP 13574]
Gtk-Message: 17:29:24.615: Failed to load module "atk-bridge"
[New LWP 13575]
[New LWP 13576]
[New LWP 13577]
Notice: could not set realtime priority.
[New LWP 13578]
[New LWP 13579]
[New LWP 13580]
[New LWP 13581]
Lv2 plugin SUMMARY: 0 of 0  loaded in 0 msecs.
[New LWP 13582]
[LWP 13582 exited]
[New LWP 13583]
[New LWP 13584]
[New LWP 13585]
Cannot load library ~/apps/squashfs-root/usr/lib/lmms/libcarlapatchbay.so: (libcarlabase.so: невозможно открыть разделяемый объектный файл: Нет такого файла или каталога)
Cannot load library ~/apps/squashfs-root/usr/lib/lmms/libcarlabase.so: (libcarla_native-plugin.so: невозможно открыть разделяемый объектный файл: Нет такого файла или каталога)
Cannot load library ~/apps/squashfs-root/usr/lib/lmms/libcarlarack.so: (libcarlabase.so: невозможно открыть разделяемый объектный файл: Нет такого файла или каталога)
[New LWP 13589]
[Detaching after fork from child process 13590]
Starting using X11Embed protocol.
unique ID: MSP2
RemotePlugin::DebugMessage: inputs: 0  output: 16
RemotePlugin::DebugMessage: creating editor
RemotePlugin::DebugMessage: editor successfully created
QObject::connect: Cannot connect (null)::subWindowActivated( QMdiSubWindow* ) to SubWindow::focusChanged( QMdiSubWindow* )
[New LWP 13632]
[Detaching after fork from child process 13633]
Starting using X11Embed protocol.
unique ID: 6ass
RemotePlugin::DebugMessage: inputs: 0  output: 2
RemotePlugin::DebugMessage: creating editor
wine: Read access denied for device L"\\??\\Z:\\", FS volume label and serial are not available.
wine: Read access denied for device L"\\??\\Z:\\", FS volume label and serial are not available.
RemotePlugin::DebugMessage: editor successfully created
QObject::connect: Cannot connect (null)::subWindowActivated( QMdiSubWindow* ) to SubWindow::focusChanged( QMdiSubWindow* )
[New LWP 13637]
[Detaching after fork from child process 13638]
Starting using X11Embed protocol.
unique ID: 4FBS
RemotePlugin::DebugMessage: inputs: 0  output: 2
RemotePlugin::DebugMessage: creating editor
RemotePlugin::DebugMessage: editor successfully created
QObject::connect: Cannot connect (null)::subWindowActivated( QMdiSubWindow* ) to SubWindow::focusChanged( QMdiSubWindow* )
[LWP 13577 exited]
[New LWP 13642]
[Detaching after fork from child process 13643]
Starting using X11Embed protocol.
unique ID: MSP2
RemotePlugin::DebugMessage: inputs: 0  output: 16
RemotePlugin::DebugMessage: creating editor
RemotePlugin::DebugMessage: editor successfully created
QObject::connect: Cannot connect (null)::subWindowActivated( QMdiSubWindow* ) to SubWindow::focusChanged( QMdiSubWindow* )
[New LWP 13650]
[Detaching after fork from child process 13651]
Starting using X11Embed protocol.
wine: Read access denied for device L"\\??\\D:\\", FS volume label and serial are not available.
wine: Read access denied for device L"\\??\\D:\\", FS volume label and serial are not available.
wine: Read access denied for device L"\\??\\D:\\", FS volume label and serial are not available.
unique ID: dskc
RemotePlugin::DebugMessage: inputs: 0  output: 2
RemotePlugin::DebugMessage: creating editor
RemotePlugin::DebugMessage: editor successfully created
QObject::connect: Cannot connect (null)::subWindowActivated( QMdiSubWindow* ) to SubWindow::focusChanged( QMdiSubWindow* )
[New LWP 13655]
[Detaching after fork from child process 13656]
Starting using X11Embed protocol.
unique ID: ncut
RemotePlugin::DebugMessage: inputs: 2  output: 2
RemotePlugin::DebugMessage: creating editor
003f:err:ole:CoGetClassObject class {4ce576fa-83dc-4f88-951c-9d0782b4e376} not registered
003f:err:ole:create_server class {4ce576fa-83dc-4f88-951c-9d0782b4e376} not registered
003f:err:ole:CoGetClassObject no class object {4ce576fa-83dc-4f88-951c-9d0782b4e376} could be created for context 0x6
RemotePlugin::DebugMessage: editor successfully created
QObject::connect: Cannot connect (null)::subWindowActivated( QMdiSubWindow* ) to SubWindow::focusChanged( QMdiSubWindow* )
wine: Read access denied for device L"\\??\\Z:\\", FS volume label and serial are not available.
noteEnd() triggered without a corresponding activate()!
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 13237, resource id: 127139283, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 13238, resource id: 127139283, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 13239, resource id: 127139283, major code: 60 (FreeGC), minor code: 0
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 9712, resource id: 127146664, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 9713, resource id: 127146664, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 9714, resource id: 127146664, major code: 60 (FreeGC), minor code: 0
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 42011, resource id: 126980464, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 42012, resource id: 126980464, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 42014, resource id: 126980464, major code: 60 (FreeGC), minor code: 0
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 61067, resource id: 127018022, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 61068, resource id: 127018022, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 61070, resource id: 127018022, major code: 60 (FreeGC), minor code: 0
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 31338, resource id: 127015853, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 31339, resource id: 127015853, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 31340, resource id: 127015853, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 31341, resource id: 127015853, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 31342, resource id: 127015853, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 31343, resource id: 127015853, major code: 60 (FreeGC), minor code: 0
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 174, resource id: 127007329, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 175, resource id: 127007329, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 176, resource id: 127007329, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 177, resource id: 127007329, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 178, resource id: 127007329, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 179, resource id: 127007329, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 180, resource id: 127007329, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 181, resource id: 127007329, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 182, resource id: 127007329, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 183, resource id: 127007329, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 184, resource id: 127007329, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 185, resource id: 127007329, major code: 60 (FreeGC), minor code: 0
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 25695, resource id: 126969818, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 25696, resource id: 126969818, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 25697, resource id: 126969818, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 25698, resource id: 126969818, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 25699, resource id: 126969818, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 25700, resource id: 126969818, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 25701, resource id: 126969818, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 25702, resource id: 126969818, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 25703, resource id: 126969818, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 25704, resource id: 126969818, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 25705, resource id: 126969818, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 25706, resource id: 126969818, major code: 60 (FreeGC), minor code: 0
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 63494, resource id: 126982545, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 63495, resource id: 126982545, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 63497, resource id: 126982545, major code: 60 (FreeGC), minor code: 0
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 36813, resource id: 126985635, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 36814, resource id: 126985635, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 36815, resource id: 126985635, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 36816, resource id: 126985635, major code: 60 (FreeGC), minor code: 0
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 17923, resource id: 126996135, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 17924, resource id: 126996135, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 17925, resource id: 126996135, major code: 60 (FreeGC), minor code: 0
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 7898, resource id: 126989506, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 7899, resource id: 126989506, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 7900, resource id: 126989506, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 7901, resource id: 126989506, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 7902, resource id: 126989506, major code: 60 (FreeGC), minor code: 0
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 21998, resource id: 126990462, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 21999, resource id: 126990462, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 22000, resource id: 126990462, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 22001, resource id: 126990462, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 22002, resource id: 126990462, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 22003, resource id: 126990462, major code: 60 (FreeGC), minor code: 0
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 27767, resource id: 127025378, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 27768, resource id: 127025378, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 27769, resource id: 127025378, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 27770, resource id: 127025378, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 27771, resource id: 127025378, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 27772, resource id: 127025378, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 27773, resource id: 127025378, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 27774, resource id: 127025378, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 27775, resource id: 127025378, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 27776, resource id: 127025378, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 27777, resource id: 127025378, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 27778, resource id: 127025378, major code: 60 (FreeGC), minor code: 0
[New LWP 16928]
[New LWP 16929]
[New LWP 16930]
[LWP 16928 exited]
[LWP 13585 exited]
[New LWP 16954]
[LWP 16929 exited]
PERFLOG |       Project Render | 198.90user, 24.77system 162.97elapsed
[LWP 16954 exited]
[New LWP 17030]
[LWP 17030 exited]
[New LWP 17039]
[LWP 16930 exited]
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 3503, resource id: 126812736, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 3504, resource id: 126812736, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 3505, resource id: 126812736, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 3506, resource id: 126812736, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 3507, resource id: 126812736, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 3508, resource id: 126812736, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 3509, resource id: 126812736, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 3510, resource id: 126812736, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 3511, resource id: 126812736, major code: 60 (FreeGC), minor code: 0
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 45067, resource id: 126794531, major code: 53 (CreatePixmap), minor code: 0
QXcbConnection: XCB error: 9 (BadDrawable), sequence: 45068, resource id: 126794531, major code: 139 (Unknown), minor code: 4
QXcbConnection: XCB error: 9 (BadDrawable), sequence: 45069, resource id: 126794531, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 9 (BadDrawable), sequence: 45070, resource id: 126794531, major code: 72 (PutImage), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 45071, resource id: 126794533, major code: 60 (FreeGC), minor code: 0
QXcbConnection: XCB error: 143 (Unknown), sequence: 45072, resource id: 126794532, major code: 139 (Unknown), minor code: 27
QXcbConnection: XCB error: 143 (Unknown), sequence: 45073, resource id: 126794532, major code: 139 (Unknown), minor code: 7
QXcbConnection: XCB error: 4 (BadPixmap), sequence: 45074, resource id: 126794531, major code: 54 (FreePixmap), minor code: 0
QXcbConnection: XCB error: 6 (BadCursor), sequence: 45075, resource id: 126794534, major code: 2 (ChangeWindowAttributes), minor code: 0
QXcbConnection: XCB error: 6 (BadCursor), sequence: 45087, resource id: 126794534, major code: 95 (FreeCursor), minor code: 0
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 57769, resource id: 126797347, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 57770, resource id: 126797347, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 57771, resource id: 126797347, major code: 60 (FreeGC), minor code: 0
QXcbConnection: XCB error: 14 (BadIDChoice), sequence: 21361, resource id: 126828627, major code: 55 (CreateGC), minor code: 0
QXcbConnection: XCB error: 13 (BadGC), sequence: 21362, resource id: 126828627, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 21363, resource id: 126828627, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 21364, resource id: 126828627, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 21365, resource id: 126828627, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 21366, resource id: 126828627, major code: 130 (Unknown), minor code: 3
QXcbConnection: XCB error: 13 (BadGC), sequence: 21367, resource id: 126828627, major code: 60 (FreeGC), minor code: 0
[New LWP 18097]
[New LWP 18098]
[New LWP 18099]
[New LWP 18100]
[LWP 18097 exited]
[LWP 18099 exited]
[LWP 17039 exited]
[New LWP 18123]
[LWP 18098 exited]
PERFLOG |       Project Render | 196.76user, 24.48system 170.63elapsed
[LWP 18123 exited]
[New LWP 18278]
[LWP 18278 exited]
[New LWP 18280]
[LWP 18100 exited]
[LWP 13655 exited]
003f:err:ole:RevokeDragDrop invalid hwnd 00010182
[LWP 13650 exited]
[LWP 13642 exited]
0036:err:ole:RevokeDragDrop invalid hwnd 000100F4
[LWP 13637 exited]
[LWP 13632 exited]
[LWP 13589 exited]
0009:err:ole:RevokeDragDrop invalid hwnd 0001005E
QProcess: Destroyed while process ("~/apps/squashfs-root/usr/lib/lmms/32/RemoteVstPlugin32") is still running.
Process error:  QProcess::ProcessError(Crashed)
Remote plugin crashed
[New LWP 18304]
[Detaching after fork from child process 18305]
Starting using X11Embed protocol.
unique ID: 6ass
RemotePlugin::DebugMessage: inputs: 0  output: 2
wine: Read access denied for device L"\\??\\Z:\\", FS volume label and serial are not available.
wine: Read access denied for device L"\\??\\Z:\\", FS volume label and serial are not available.
RemotePlugin::DebugMessage: creating editor
RemotePlugin::DebugMessage: editor successfully created
QObject::connect: Cannot connect (null)::subWindowActivated( QMdiSubWindow* ) to SubWindow::focusChanged( QMdiSubWindow* )
[New LWP 18310]
[Detaching after fork from child process 18311]
Starting using X11Embed protocol.
unique ID: ncut
RemotePlugin::DebugMessage: inputs: 2  output: 2
RemotePlugin::DebugMessage: creating editor
0049:err:ole:CoGetClassObject class {4ce576fa-83dc-4f88-951c-9d0782b4e376} not registered
0049:err:ole:create_server class {4ce576fa-83dc-4f88-951c-9d0782b4e376} not registered
0049:err:ole:CoGetClassObject no class object {4ce576fa-83dc-4f88-951c-9d0782b4e376} could be created for context 0x6
RemotePlugin::DebugMessage: editor successfully created
QObject::connect: Cannot connect (null)::subWindowActivated( QMdiSubWindow* ) to SubWindow::focusChanged( QMdiSubWindow* )
[New LWP 18322]
[Detaching after fork from child process 18323]
Starting using X11Embed protocol.
unique ID: ncut
RemotePlugin::DebugMessage: inputs: 2  output: 2
RemotePlugin::DebugMessage: creating editor
0050:err:ole:CoGetClassObject class {4ce576fa-83dc-4f88-951c-9d0782b4e376} not registered
0050:err:ole:create_server class {4ce576fa-83dc-4f88-951c-9d0782b4e376} not registered
0050:err:ole:CoGetClassObject no class object {4ce576fa-83dc-4f88-951c-9d0782b4e376} could be created for context 0x6
RemotePlugin::DebugMessage: editor successfully created
QObject::connect: Cannot connect (null)::subWindowActivated( QMdiSubWindow* ) to SubWindow::focusChanged( QMdiSubWindow* )
[New LWP 18331]
[Detaching after fork from child process 18332]
Starting using X11Embed protocol.
unique ID: ncut
RemotePlugin::DebugMessage: inputs: 2  output: 2
RemotePlugin::DebugMessage: creating editor
0057:err:ole:CoGetClassObject class {4ce576fa-83dc-4f88-951c-9d0782b4e376} not registered
0057:err:ole:create_server class {4ce576fa-83dc-4f88-951c-9d0782b4e376} not registered
0057:err:ole:CoGetClassObject no class object {4ce576fa-83dc-4f88-951c-9d0782b4e376} could be created for context 0x6
RemotePlugin::DebugMessage: editor successfully created
QObject::connect: Cannot connect (null)::subWindowActivated( QMdiSubWindow* ) to SubWindow::focusChanged( QMdiSubWindow* )
[New LWP 18340]
[Detaching after fork from child process 18341]
Starting using X11Embed protocol.
wine: Read access denied for device L"\\??\\D:\\", FS volume label and serial are not available.
wine: Read access denied for device L"\\??\\D:\\", FS volume label and serial are not available.
wine: Read access denied for device L"\\??\\D:\\", FS volume label and serial are not available.
unique ID: dskc
RemotePlugin::DebugMessage: inputs: 0  output: 2
RemotePlugin::DebugMessage: creating editor
RemotePlugin::DebugMessage: editor successfully created
QObject::connect: Cannot connect (null)::subWindowActivated( QMdiSubWindow* ) to SubWindow::focusChanged( QMdiSubWindow* )
wine: Read access denied for device L"\\??\\Z:\\", FS volume label and serial are not available.
--Type <RET> for more, q to quit, c to continue without paging--

Thread 32 "Mixer::fifoWrit" received signal SIGSEGV, Segmentation fault.
[Switching to LWP 18280]
0x00007ffff4fe2e26 in ?? ()
(gdb) 

[zonkmachine]

Thread 32 "Mixer::fifoWrit" received signal SIGSEGV, Segmentation fault.
[Switching to LWP 18280]
0x00007ffff4fe2e26 in ?? ()
(gdb) 

Thanks! Can you please give us the output of the command
bt full
type it at the prompt (gdb)

[zeganstyl]

@zonkmachine, I forgot about that and closed terminal :(
Next time.

[zeganstyl]

bt full

RemotePlugin::DebugMessage: inputs: 0  output: 2
RemotePlugin::DebugMessage: creating editor
RemotePlugin::DebugMessage: editor successfully created
QObject::connect: Cannot connect (null)::subWindowActivated( QMdiSubWindow* ) to SubWindow::focusChanged( QMdiSubWindow* )
wine: Read access denied for device L"\\??\\Z:\\", FS volume label and serial are not available.

Thread 13 "Mixer::fifoWrit" received signal SIGSEGV, Segmentation fault.
[Switching to LWP 23151]
--Type <RET> for more, q to quit, c to continue without paging--c
0x00007ffff4fe2df2 in ?? ()
(gdb) bt full
#0  0x00007ffff4fe2df2 in ?? ()
No symbol table info available.
#1  0x00007fffa37fca60 in ?? ()
No symbol table info available.
#2  0xd604909550505600 in ?? ()
No symbol table info available.
#3  0x00007fffa37fcb70 in ?? ()
No symbol table info available.
#4  0xd604909550505600 in ?? ()
No symbol table info available.
#5  0x00007fffa37fca60 in ?? ()
No symbol table info available.
#6  0x00007fffa37fcb70 in ?? ()
No symbol table info available.
#7  0x00007fffeea48820 in ?? ()
No symbol table info available.
#8  0x00007fff94008af0 in ?? ()
No symbol table info available.
#9  0x000000000000e4c0 in ?? ()
No symbol table info available.
#10 0x0000000000597680 in TrackContainer::automatedValuesFromTracks (
    tracks=..., time=..., tcoNum=tcoNum@entry=-1)
    at /root/project/src/core/TrackContainer.cpp:293
--Type <RET> for more, q to quit, c to continue without paging--c
        p = <optimized out>
        tco = 0x7fffeea48820
        __for_range = @0x7fffa37fca50: {d = 0x7fff940087d0}
        __for_begin = 0x7fff94008af0
        __for_end = <optimized out>
        tcos = {d = 0x7fff940087d0}
        valueMap = {d = 0x0}
#11 0x000000000058a581 in Song::automatedValuesAt (this=0xcd4780, time=..., tcoNum=-1) at /root/project/src/core/Song.cpp:844
No locals.
#12 0x000000000058b4e3 in Song::processAutomations (this=this@entry=0xcd4780, tracklist=..., timeStart=...) at /root/project/src/core/Song.cpp:383
        values = {d = 0x7ffff54ac280 <QMapDataBase::shared_null>}
        recordedModels = {q_hash = {{d = 0x7ffff546c3a0 <QHashData::shared_null>, e = 0x7ffff546c3a0 <QHashData::shared_null>}}}
        container = 0xcd4780
        tcoNum = <optimized out>
        tracks = {d = 0xcba3ec}
#13 0x000000000058c263 in Song::processNextBuffer (this=0xcd4780) at /root/project/src/core/Song.cpp:338
        frameOffsetInTick = 0
        framesUntilNextPeriod = <optimized out>
        framesUntilNextTick = <optimized out>
        framesToPlay = <optimized out>
        trackList = {d = 0x3aa5390}
        clipNum = -1
        enforceLoop = <optimized out>
        timeline = 0x156ff90
        loopEnabled = <optimized out>
        framesPerTick = <optimized out>
        framesPerPeriod = <optimized out>
        frameOffsetInPeriod = 17
#14 0x0000000000559998 in Mixer::renderNextBuffer (this=0xefaec0) at /root/project/src/core/Mixer.cpp:376
        it_rem = <optimized out>
        fxMixer = <optimized out>
#15 0x0000000000559d0c in Mixer::fifoWriter::run (this=0xf61710) at /root/project/src/core/Mixer.cpp:1263
        buffer = 0x7fff94008be0
        b = <optimized out>
        frames = <optimized out>
#16 0x00007ffff51c93f8 in ?? () from ~/apps/squashfs-root/usr/lib/libQt5Core.so.5
No symbol table info available.
#17 0x00007ffff7f8d609 in ?? ()
No symbol table info available.
#18 0x0000000000000000 in ?? ()
No symbol table info available.
(gdb) 

thread apply all bt full

(gdb) thread apply all bt full

Thread 18 (LWP 23225):
#0  0x00007ffff4e42aff in ?? ()
No symbol table info available.
#1  0x00007fff7c005220 in ?? ()
No symbol table info available.
#2  0x00007fff7c005220 in ?? ()
No symbol table info available.
#3  0x0000000000000002 in ?? ()
No symbol table info available.
#4  0xffffffff00000001 in ?? ()
No symbol table info available.
#5  0x00007fff7c000c30 in ?? ()
No symbol table info available.
#6  0x00007ffff4bf636e in ?? ()
No symbol table info available.
#7  0x00007fff7c003200 in ?? ()
No symbol table info available.
#8  0x0000000190da9b60 in ?? ()
No symbol table info available.
#9  0xffffffff7fffffff in ?? ()
No symbol table info available.
#10 0xd604909550505600 in ?? ()
No symbol table info available.
#11 0x00007ffff546b260 in ?? () from ~/apps/squashfs-root/usr/lib/libQt5Core.so.5
No symbol table info available.
#12 0x00007fff7c000b80 in ?? ()
No symbol table info available.
#13 0x00007fff7c000c30 in ?? ()
No symbol table info available.
#14 0x0000000000000001 in ?? ()
No symbol table info available.
#15 0x00007fff7c000b60 in ?? ()
No symbol table info available.
#16 0x0000000000000000 in ?? ()
No symbol table info available.

Thread 17 (LWP 23216):
#0  0x00007ffff4e42aff in ?? ()
No symbol table info available.
#1  0x00007fff880041c0 in ?? ()
No symbol table info available.
#2  0x00007fff880041c0 in ?? ()
No symbol table info available.
#3  0x0000000000000002 in ?? ()
No symbol table info available.
#4  0xffffffff00000001 in ?? ()
No symbol table info available.
#5  0x00007fff88000c30 in ?? ()
No symbol table info available.
#6  0x00007ffff4bf636e in ?? ()
No symbol table info available.
#7  0x00007fff88004a00 in ?? ()
--Type <RET> for more, q to quit, c to continue without paging--c
No symbol table info available.
#8  0x0000000100000001 in ?? ()
No symbol table info available.
#9  0xffffffff7fffffff in ?? ()
No symbol table info available.
#10 0xd604909550505600 in ?? ()
No symbol table info available.
#11 0x00007ffff546b260 in ?? () from ~/apps/squashfs-root/usr/lib/libQt5Core.so.5
No symbol table info available.
#12 0x00007fff88000b80 in ?? ()
No symbol table info available.
#13 0x00007fff88000c30 in ?? ()
No symbol table info available.
#14 0x0000000000000001 in ?? ()
No symbol table info available.
#15 0x00007fff88000b60 in ?? ()
No symbol table info available.
#16 0x0000000000000000 in ?? ()
No symbol table info available.

Thread 16 (LWP 23207):
#0  0x00007ffff4e42aff in ?? ()
No symbol table info available.
#1  0x00007fff84005220 in ?? ()
No symbol table info available.
#2  0x00007fff84005220 in ?? ()
No symbol table info available.
#3  0x0000000000000002 in ?? ()
No symbol table info available.
#4  0xffffffff00000001 in ?? ()
No symbol table info available.
#5  0x00007fff84000c30 in ?? ()
No symbol table info available.
#6  0x00007ffff4bf636e in ?? ()
No symbol table info available.
#7  0x00007fff84003200 in ?? ()
No symbol table info available.
#8  0x0000000191dabb60 in ?? ()
No symbol table info available.
#9  0xffffffff7fffffff in ?? ()
No symbol table info available.
#10 0xd604909550505600 in ?? ()
No symbol table info available.
#11 0x00007ffff546b260 in ?? () from ~/apps/squashfs-root/usr/lib/libQt5Core.so.5
No symbol table info available.
#12 0x00007fff84000b80 in ?? ()
No symbol table info available.
#13 0x00007fff84000c30 in ?? ()
No symbol table info available.
#14 0x0000000000000001 in ?? ()
No symbol table info available.
#15 0x00007fff84000b60 in ?? ()
No symbol table info available.
#16 0x0000000000000000 in ?? ()
No symbol table info available.

Thread 15 (LWP 23196):
#0  0x00007ffff4e42aff in ?? ()
No symbol table info available.
#1  0x00007fffd8004350 in ?? ()
No symbol table info available.
#2  0x00007fffd8004350 in ?? ()
No symbol table info available.
#3  0x0000000000000002 in ?? ()
No symbol table info available.
#4  0xffffffff00000001 in ?? ()
No symbol table info available.
#5  0x00007fffd8000c10 in ?? ()
No symbol table info available.
#6  0x00007ffff4bf636e in ?? ()
No symbol table info available.
#7  0x00007fffd8004930 in ?? ()
No symbol table info available.
#8  0x0000000100000001 in ?? ()
No symbol table info available.
#9  0xffffffff7fffffff in ?? ()
No symbol table info available.
#10 0xd604909550505600 in ?? ()
No symbol table info available.
#11 0x00007ffff546b260 in ?? () from ~/apps/squashfs-root/usr/lib/libQt5Core.so.5
No symbol table info available.
#12 0x00007fffd8000b60 in ?? ()
No symbol table info available.
#13 0x00007fffd8000c10 in ?? ()
No symbol table info available.
#14 0x0000000000000001 in ?? ()
No symbol table info available.
#15 0x00007fffd8001360 in ?? ()
No symbol table info available.
#16 0x0000000000000000 in ?? ()
No symbol table info available.

Thread 14 (LWP 23155):
#0  0x00007ffff4e42aff in ?? ()
No symbol table info available.
#1  0x00007fff8c003530 in ?? ()
No symbol table info available.
#2  0x00007fff8c003530 in ?? ()
No symbol table info available.
#3  0x0000000000000002 in ?? ()
No symbol table info available.
#4  0xffffffff00000001 in ?? ()
No symbol table info available.
#5  0x00007fff8c000c30 in ?? ()
No symbol table info available.
#6  0x00007ffff4bf636e in ?? ()
No symbol table info available.
#7  0x00007fff8c003d70 in ?? ()
No symbol table info available.
#8  0x0000000100000001 in ?? ()
No symbol table info available.
#9  0xffffffff7fffffff in ?? ()
No symbol table info available.
#10 0xd604909550505600 in ?? ()
No symbol table info available.
#11 0x0000000000000000 in ?? ()
No symbol table info available.

Thread 13 (LWP 23151):
#0  0x00007ffff4fe2df2 in ?? ()
No symbol table info available.
#1  0x00007fffa37fca60 in ?? ()
No symbol table info available.
#2  0xd604909550505600 in ?? ()
No symbol table info available.
#3  0x00007fffa37fcb70 in ?? ()
No symbol table info available.
#4  0xd604909550505600 in ?? ()
No symbol table info available.
#5  0x00007fffa37fca60 in ?? ()
No symbol table info available.
#6  0x00007fffa37fcb70 in ?? ()
No symbol table info available.
#7  0x00007fffeea48820 in ?? ()
No symbol table info available.
#8  0x00007fff94008af0 in ?? ()
No symbol table info available.
#9  0x000000000000e4c0 in ?? ()
No symbol table info available.
#10 0x0000000000597680 in TrackContainer::automatedValuesFromTracks (tracks=..., time=..., tcoNum=tcoNum@entry=-1) at /root/project/src/core/TrackContainer.cpp:293
        p = <optimized out>
        tco = 0x7fffeea48820
        __for_range = @0x7fffa37fca50: {d = 0x7fff940087d0}
        __for_begin = 0x7fff94008af0
        __for_end = <optimized out>
        tcos = {d = 0x7fff940087d0}
        valueMap = {d = 0x0}
#11 0x000000000058a581 in Song::automatedValuesAt (this=0xcd4780, time=..., tcoNum=-1) at /root/project/src/core/Song.cpp:844
No locals.
#12 0x000000000058b4e3 in Song::processAutomations (this=this@entry=0xcd4780, tracklist=..., timeStart=...) at /root/project/src/core/Song.cpp:383
        values = {d = 0x7ffff54ac280 <QMapDataBase::shared_null>}
        recordedModels = {q_hash = {{d = 0x7ffff546c3a0 <QHashData::shared_null>, e = 0x7ffff546c3a0 <QHashData::shared_null>}}}
        container = 0xcd4780
        tcoNum = <optimized out>
        tracks = {d = 0xcba3ec}
#13 0x000000000058c263 in Song::processNextBuffer (this=0xcd4780) at /root/project/src/core/Song.cpp:338
        frameOffsetInTick = 0
        framesUntilNextPeriod = <optimized out>
        framesUntilNextTick = <optimized out>
        framesToPlay = <optimized out>
        trackList = {d = 0x3aa5390}
        clipNum = -1
        enforceLoop = <optimized out>
        timeline = 0x156ff90
        loopEnabled = <optimized out>
        framesPerTick = <optimized out>
        framesPerPeriod = <optimized out>
        frameOffsetInPeriod = 17
#14 0x0000000000559998 in Mixer::renderNextBuffer (this=0xefaec0) at /root/project/src/core/Mixer.cpp:376
        it_rem = <optimized out>
        fxMixer = <optimized out>
#15 0x0000000000559d0c in Mixer::fifoWriter::run (this=0xf61710) at /root/project/src/core/Mixer.cpp:1263
        buffer = 0x7fff94008be0
        b = <optimized out>
        frames = <optimized out>
#16 0x00007ffff51c93f8 in ?? () from ~/apps/squashfs-root/usr/lib/libQt5Core.so.5
No symbol table info available.
#17 0x00007ffff7f8d609 in ?? ()
No symbol table info available.
#18 0x0000000000000000 in ?? ()
No symbol table info available.

Thread 12 (LWP 23150):
#0  0x00007ffff4e42aff in ?? ()
No symbol table info available.
#1  0x0000000000000010 in ?? ()
No symbol table info available.
#2  0x00007fff9c0029e0 in ?? ()
No symbol table info available.
#3  0x0000000000000002 in ?? ()
No symbol table info available.
#4  0x000000faf7ffe190 in ?? ()
No symbol table info available.
#5  0x00000000000003f7 in ?? ()
No symbol table info available.
#6  0x00000000005beae6 in poll (__timeout=250, __nfds=2, __fds=0x7fff9c0029e0) at /usr/include/x86_64-linux-gnu/bits/poll2.h:46
No locals.
#7  MidiAlsaSeq::run (this=0xf5ebf0) at /root/project/src/core/midi/MidiAlsaSeq.cpp:472
        pollRet = <optimized out>
        pollfd_count = 2
        pollfd_set = 0x7fff9c0029e0
        __PRETTY_FUNCTION__ = "virtual void MidiAlsaSeq::run()"
#8  0x00007ffff51c93f8 in ?? () from ~/apps/squashfs-root/usr/lib/libQt5Core.so.5
No symbol table info available.
#9  0x00007ffff7f8d609 in ?? ()
No symbol table info available.
#10 0x0000000000000000 in ?? ()
No symbol table info available.

Thread 11 (LWP 23149):
#0  0x00007ffff4e42bf6 in ?? ()
No symbol table info available.
#1  0x000000000108d8d0 in ?? ()
No symbol table info available.
#2  0x00007fffa8000fe0 in ?? ()
No symbol table info available.
#3  0x0000000000000003 in ?? ()
No symbol table info available.
#4  0x0000000000000000 in ?? ()
No symbol table info available.

Thread 9 (LWP 23147):
#0  0x00007ffff7f94376 in ?? ()
No symbol table info available.
#1  0x000000000003b831 in ?? ()
No symbol table info available.
#2  0x0000008150505600 in ?? ()
No symbol table info available.
#3  0x0000000000000001 in ?? ()
No symbol table info available.
#4  0x0000000000cb1138 in ?? ()
No symbol table info available.
#5  0x0000000000000004 in ?? ()
No symbol table info available.
#6  0x0000000000077063 in ?? ()
No symbol table info available.
#7  0x0000000000cb113c in ?? ()
No symbol table info available.
#8  0x0000000000a06058 in MixerWorkerThread::globalJobQueue ()
No symbol table info available.
#9  0x00007ffff7f94050 in ?? ()
No symbol table info available.
#10 0x00007fffd0f4cba0 in ?? ()
No symbol table info available.
#11 0x00007fffbc004a50 in ?? ()
No symbol table info available.
#12 0x0000000000000000 in ?? ()
No symbol table info available.

Thread 8 (LWP 23146):
#0  0x00007ffff7f94376 in ?? ()
No symbol table info available.
#1  0x000000000003b832 in ?? ()
No symbol table info available.
#2  0x0000008150505600 in ?? ()
No symbol table info available.
#3  0x0000000000000001 in ?? ()
No symbol table info available.
#4  0x0000000000cb1138 in ?? ()
No symbol table info available.
#5  0x0000000000000004 in ?? ()
No symbol table info available.
#6  0x0000000000077065 in ?? ()
No symbol table info available.
#7  0x0000000000cb113c in ?? ()
No symbol table info available.
#8  0x0000000000a06060 in MixerWorkerThread::globalJobQueue ()
No symbol table info available.
#9  0x00007ffff7f94050 in ?? ()
No symbol table info available.
#10 0x00007fffd174dba0 in ?? ()
No symbol table info available.
#11 0x00007fffc80059a0 in ?? ()
No symbol table info available.
#12 0x0000000000000000 in ?? ()
No symbol table info available.

Thread 7 (LWP 23145):
#0  0x00007ffff7f94376 in ?? ()
No symbol table info available.
#1  0x000000000003b830 in ?? ()
No symbol table info available.
#2  0x0000008100000000 in ?? ()
No symbol table info available.
#3  0x0000000000000001 in ?? ()
No symbol table info available.
#4  0x0000000000cb1138 in ?? ()
No symbol table info available.
#5  0x0000000000000004 in ?? ()
No symbol table info available.
#6  0x0000000000077061 in ?? ()
No symbol table info available.
#7  0x0000000000cb113c in ?? ()
No symbol table info available.
#8  0x00000000005243cf in EffectChain::processAudioBuffer (this=0x7fffd1f4eb80, _buf=0xcb1100, _frames=<optimized out>, hasInputNoise=40) at /root/project/src/core/EffectChain.cpp:200
        it = 0xcb1154
        moreEffects = false
#9  0xd604909550505600 in ?? ()
No symbol table info available.
#10 0x000000003e40e1b0 in ?? ()
No symbol table info available.
#11 0x0000000000cb1100 in ?? ()
No symbol table info available.
#12 0xffffffffffffffff in ?? ()
No symbol table info available.
#13 0xfffffffffff0bdc0 in ?? ()
No symbol table info available.
#14 0x0000000000cb1128 in ?? ()
No symbol table info available.
#15 0x0000000000000000 in ?? ()
No symbol table info available.

Thread 6 (LWP 23144):
#0  0x00007ffff4e42aff in ?? ()
No symbol table info available.
#1  0x00007fffcc0025e0 in ?? ()
No symbol table info available.
#2  0x00007fffcc0025e0 in ?? ()
No symbol table info available.
#3  0x0000000000000003 in ?? ()
No symbol table info available.
#4  0xffffffff00000001 in ?? ()
No symbol table info available.
#5  0x00007fffcc000c30 in ?? ()
No symbol table info available.
#6  0x00007ffff4bf636e in ?? ()
No symbol table info available.
#7  0x0000000000000000 in ?? ()
No symbol table info available.

Thread 4 (LWP 23140):
#0  0x00007ffff4e42aff in ?? ()
No symbol table info available.
#1  0x0000000000d48650 in ?? ()
No symbol table info available.
#2  0x0000000000d48650 in ?? ()
No symbol table info available.
#3  0x0000000000000002 in ?? ()
No symbol table info available.
#4  0xffffffff00000001 in ?? ()
No symbol table info available.
#5  0x0000000000d46050 in ?? ()
No symbol table info available.
#6  0x00007ffff4bf636e in ?? ()
No symbol table info available.
#7  0x0000000000000001 in ?? ()
No symbol table info available.
#8  0x0000000100d46020 in ?? ()
No symbol table info available.
#9  0xffffffff7fffffff in ?? ()
No symbol table info available.
#10 0xd604909550505600 in ?? ()
No symbol table info available.
#11 0x0000000000d46050 in ?? ()
No symbol table info available.
#12 0x0000000000d46148 in ?? ()
No symbol table info available.
#13 0x0000000000d46140 in ?? ()
No symbol table info available.
#14 0x0000000000d4614c in ?? ()
No symbol table info available.
#15 0x00007fffffffc26f in ?? ()
No symbol table info available.
#16 0x00007fffffffc300 in ?? ()
No symbol table info available.
#17 0x00007fffe2ef8e00 in ?? ()
No symbol table info available.
#18 0x00007ffff4bf66f3 in ?? ()
No symbol table info available.
#19 0x00007fffd4001400 in ?? ()
No symbol table info available.
#20 0x0000000000d46020 in ?? ()
No symbol table info available.
#21 0x0000000000000000 in ?? ()
No symbol table info available.

Thread 3 (LWP 23139):
#0  0x00007ffff4e42aff in ?? ()
No symbol table info available.
#1  0x0000000000d35330 in ?? ()
No symbol table info available.
#2  0x0000000000d35330 in ?? ()
No symbol table info available.
#3  0x0000000000000002 in ?? ()
No symbol table info available.
#4  0xffffffff00000001 in ?? ()
No symbol table info available.
#5  0x0000000000d36840 in ?? ()
No symbol table info available.
#6  0x00007ffff4bf636e in ?? ()
No symbol table info available.
#7  0x0000000000000000 in ?? ()
No symbol table info available.

Thread 2 (LWP 23138):
#0  0x00007ffff4e42aff in ?? ()
No symbol table info available.
#1  0x0000000000000000 in ?? ()
No symbol table info available.

Thread 1 (LWP 23134):
#0  0x00007ffff7a97751 in QWidgetPrivate::sendPendingMoveAndResizeEvents(bool, bool) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#1  0x00007ffff7a97764 in QWidgetPrivate::sendPendingMoveAndResizeEvents(bool, bool) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#2  0x00007ffff7a97764 in QWidgetPrivate::sendPendingMoveAndResizeEvents(bool, bool) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#3  0x00007ffff7a97764 in QWidgetPrivate::sendPendingMoveAndResizeEvents(bool, bool) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#4  0x00007ffff7a97764 in QWidgetPrivate::sendPendingMoveAndResizeEvents(bool, bool) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#5  0x00007ffff7a97764 in QWidgetPrivate::sendPendingMoveAndResizeEvents(bool, bool) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#6  0x00007ffff7a97764 in QWidgetPrivate::sendPendingMoveAndResizeEvents(bool, bool) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#7  0x00007ffff7a97764 in QWidgetPrivate::sendPendingMoveAndResizeEvents(bool, bool) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#8  0x00007ffff7a9b92b in QWidgetPrivate::prepareToRender(QRegion const&, QFlags<QWidget::RenderFlag>) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#9  0x00007ffff7a9c4df in QWidget::render(QPainter*, QPoint const&, QRegion const&, QFlags<QWidget::RenderFlag>) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#10 0x00007ffff7a9c86b in QWidget::render(QPaintDevice*, QPoint const&, QRegion const&, QFlags<QWidget::RenderFlag>) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#11 0x00007ffff7a9ca94 in ?? () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#12 0x00007ffff7df0af7 in QGraphicsEffectSource::pixmap(Qt::CoordinateSystem, QPoint*, QGraphicsEffect::PixmapPadMode) const () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#13 0x00007ffff7df0b9a in QGraphicsEffect::sourcePixmap(Qt::CoordinateSystem, QPoint*, QGraphicsEffect::PixmapPadMode) const () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#14 0x00007ffff7df1011 in QGraphicsDropShadowEffect::draw(QPainter*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#15 0x00007ffff7a9862d in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#16 0x00007ffff7a98c2c in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#17 0x00007ffff7a98b19 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#18 0x00007ffff7a97aa1 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#19 0x00007ffff7a98c2c in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#20 0x00007ffff7a98b19 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#21 0x00007ffff7a98b19 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#22 0x00007ffff7a97aa1 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#23 0x00007ffff7a98c2c in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#24 0x00007ffff7a97aa1 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#25 0x00007ffff7a98c2c in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#26 0x00007ffff7a97aa1 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#27 0x00007ffff7a98c2c in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#28 0x00007ffff7a97aa1 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#29 0x00007ffff7a98c2c in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#30 0x00007ffff7a97aa1 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#31 0x00007ffff7a98c2c in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#32 0x00007ffff7a97aa1 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#33 0x00007ffff7a6724e in ?? () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#34 0x00007ffff7a6743f in ?? () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#35 0x00007ffff7a86d1f in QWidgetPrivate::syncBackingStore() () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#36 0x00007ffff7a9eb78 in QWidget::event(QEvent*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#37 0x00007ffff7bb87eb in QMainWindow::event(QEvent*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#38 0x00007ffff7a5921c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#39 0x00007ffff7a5e756 in QApplication::notify(QObject*, QEvent*) () from ~/apps/squashfs-root/usr/lib/libQt5Widgets.so.5
No symbol table info available.
#40 0x00007ffff539e618 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from ~/apps/squashfs-root/usr/lib/libQt5Core.so.5
No symbol table info available.
#41 0x00007ffff53a04da in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () from ~/apps/squashfs-root/usr/lib/libQt5Core.so.5
No symbol table info available.
#42 0x00007ffff53f3af3 in ?? () from ~/apps/squashfs-root/usr/lib/libQt5Core.so.5
No symbol table info available.
#43 0x00007ffff4bf617d in ?? ()
No symbol table info available.
#44 0xffffffffffffd5c0 in ?? ()
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#45 0x0000000000000000 in ?? ()
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(gdb) 

[PhysSong]

It looks like a BB clip was removed while TrackContainer::automatedValuesFromTracks function is being executed sodynamic_cast was applied to freed memory address. It looks like proper synchronization between UI thread and rendering thread is missing in removal of BB clips.

[PhysSong]

I further investigated this issue. TrackContentObjectView::remove calls deleteLater for a TrackContentObject instance. deleteLater can't protect from deletion while the audio rendering thread is trying to access it.

To reproduce, you can try removing all BB clips at once while playing:
bbcrash.mmp.zip

[asmrtfm]

This has burned me so many times, now I instinctively press control+s before every middle-mouse button click even when I'm not in LMMS, lol.
Realistically, I would say 1/10 middle mouse clicks "causes" a crash.