TV/DVD on 16:9 board-monitor

[X5_44_v8_nl]

Hello all,

I have one question regarding the on board 16:9 NAV screen.
I'm installing a DVD player and I want to be able to get the image on the onboard 16:9 screen.
I do not want to use the input of my oem tv-tuner (because of mono-sound) and i do not want to use aftermarket devices. I just want to tap into the wiring harness and get the dvd image on the oem screen.

Do you know if this is possible? I assume the oem tv tuner also communicates with the onboard screen using an rgb or composite signal, so I do not see why it would not be possible.

any suggestions?