Full Screen Playback on wrong monitor and wrong size

I use a 3 monitor setup, and the right screen as playback monitor.

Suddenly, the full screen playback does not show on the assigned screen, but plays on the main (middle) screen in a strange overlaying postition of the program monitor (see image attached)

I have tried deactivating playback, activating, reboot, Nvidia Driver update...

This issue is new, and shows in all new projects. Old projects work normally funny enough.

Anybody can help with this issue?

Thanks!