(M1 MacBook Air clamshell) Black screen with sound when fullscreen

[siren128]

Hello,

currently I have my M1 MacBook Air connected to my M32u monitor via usb-c.
I can play movies when not in full screen.
When I command+F into fullscreen, it temporarily (for Like 2 seconds) goes to fullscreen, but then becomes a black screen, while sound is still playing.
My VLC version is Version 3.0.16 Vetinari.

I've tried resetting, reinstalling, but cannot get this to work.
I've played the video in a different app in full screen and it works fine so I assume its a VLC settings issue.
Would greatly appreciate some advice to fix this issue.