I'm not getting any video output anymore from the composite plug, it worked earlier today but the screen had these diagonal lines running across it. After searching abit i found out that it might be a ground loop problem, after fiddeling with the wiring a bit, the video-output stopped working all together.
I tried different screens, pi's and cables but it's not working anymore, i also tried editing the boot/config.txt to the correct settings but that didn't help. The HDMI output still works, the screen also turns on and shows "AV1" but no video.
So.... i'm a bit stuck right now, if anyone knows a solution for this i would love to hear it.