Twitching of constrained rigid bodies

[Scapior]

Hello.
I have a problem with a bunch of constrained rigid bodies. After falling to the floor they starts rotating around instead of going to sleep, as if they had an applied drive.

The issue is observed in 5.6.1 with both TGS and PGS solvers (CPU).

issue.mp4

The reproduce is here: https://github.com/Scapior/PhysX/blob/main/physx/snippets/snippethelloworld/
SnippetHelloWorld.cpp - logic
RagdollData.h - rigid bodies data

Also, if uncomment creation of all shapes (line 78 in SnippetHelloWorld.cpp), the whole system will instantly fly off into space.

PxConstraintFlag::eCOLLISION_ENABLED is set to false, so there is shouldn't be a child-parent collision.

Is this a problem in the bodies setup, or there are any pitfalls of PhysX?

Thank you in advance.