Likely a safety issue: Video_In, is disabled unless reverse is engaged or handbrake is on. No video_In to distract driver while driving.
There usually is a setup override in your setup or you have to dummy up a reverse signal or handbrake signal, to enable video_in.
You can also check if a handbrake signal is required to enable VideoIn. A safety issue to assure handbrake is on before you play Video Movies. The device doesnt know if you play movies or input reverse camera.
Auf deinem Software version photo:
RVS is likely Reverse. Rueckwaerts.
PKB is likely Parking Brake. Handbremse
these are likely the signals controlling the Video_In signal. Try all four combinations.
Just an educated guess.
