Scutters, thanks for youre advice.
TV is the default audio device and is the only one active in windows.
I set the other screen as default audio device, and all is good. (But thats a tiny little screen with squeeky sound)
I tried to set the sound options different at the new tv, and when i turn OFF all sound options (Dolby Atmos, surround sound...ALL) i still have USUALLY no sound.
I thought it was somewhere in the settings of the tv. i'll keep them off, but the problem persists.
attached are 2 video's, one when the soud is ok, one with the "hickup" and no sound. all recorded within 1 minute from eachother.
I just start Pinball X, nothing more, nothing less.....
With_sound.mp4
without_sound.mp4