[BUG] Interaction with a KVM switch

[sesquipedality]

Describe the bug

When using LGTV Companion with a KVM switch, the TV is turned off when the inactive PC powers down.

How to reproduce the bug?

Attach two PCs to a single input of the PC using a KVM. Turn both on. Switch from PC A to PC B, wait until PC A suspends. Screen will turn off when using PC B.

What was the expected behavior

LGTV companion should only turn off the TV if it is receiving a signal from it.

What is your system?

Win 11 24H2, LG 55CX OLED

Log file and screenshots

Not applicable.

I would be happy if there could be a configuration option not to send power down events when the PC is not connected to the TV, if that is possible.

Thanks

[dechamps]

You may want to take a look at the discussion in #50. In particular, if you can change your setup to plug your two PCs to two separate inputs of the TV (instead of going through the KVM), you can use the "process events only when the TV has this source selected" option in LGTVCompanion. Using LGTVDeviceListener you can make the TV follow the USB switching events so that the TV "follows" your mouse and keyboard.

[sesquipedality]

Thanks. I don't think that would help in my situation as the KVM connects to the TV through a sound bar, so there isn't a sensible way to get the different PCs to use different inputs without losing decent sound on one of the PCs, which would be far from ideal.

It looks as though it ought to be possible to implement logic for whether a particular display in present based on display name, one of the answers to https://stackoverflow.com/questions/14286631/is-there-a-way-to-detect-if-a-monitor-is-plugged-in is doing something quite similar. I appreciate this might be a low coding priority, given the unusual setup, but I do think this would be a more reliable way of implementing things than detecting the presence of a mouse or keyboard if implementing such an option were possible.

I would write a patch myself, but really my C++ is so rusty as to be non-existent, unfortunately, and I know nothing about writing for a Windows environment.

[dechamps]

I don't think that would help in my situation as the KVM connects to the TV through a sound bar, so there isn't a sensible way to get the different PCs to use different inputs without losing decent sound on one of the PCs

Instead of going through a sound bar, have you considered having the TV forward the audio to the sound bar through S/PDIF or ARC?

Connecting sources directly to the TV may bring other benefits. For example, you may be struggling to get 2160p@120Hz/HDR/10bit to pass through these middleboxes, but with a direct connection that wouldn't be an issue.

[sesquipedality]

I have considered many possible combinations. Computer -> Sound Bar -> TV was the one that actually worked. The other way round didn't, unfortunately. And HDMI 2.1 passes though fine (from the computer which supports it).