Just got a new Wildwood and this forum has been so helpful, I thought I'd join and post this to help someone else. I didn't see it in my search.
I connected our new TV and could not get the mounted DVD player to work. After a lot of tinkering and head scratching, I decided to take the DVD player out of the wall. You have to be careful getting the trim piece off, but it was easy after that. Sure enough...
There is an AV cord (red, white, yellow) that goes from the DVD player to a wall plate that you connect the TV to. That cord was plugged into the DVD player's "AV IN" instead of the "AV OUT".
New RV Kink #1 straightened out
DVD player and TV hookups shown here: