I found what caused my mouse to behave erratically in VR:
As a matter of fact, I have two pointing devices connected to my PC. One is a trackball in my rig, used for VR flying. The other one is a regular mouse that sits close to the PC, used for non-flightsim interaction.
After I disconnected that second mouse, my trackball is again rock steady in VR. I have not investigated yet, if the mouse I removed is faulty, or if it just picked up vibrations from a loudspleaker that was very close to it.
But the main thing is: my trackball works again in VR, and that is with a motion rig AND and a buttkicker active…
I thought I share this - maybe it helps others…
PD: the regular FS2024 related VR mouse problems unfortunately persist. I rally hope MS takes note of this and addresses the problem in one of the upcoming bug fixes!