We had that problem for a while. Someone on this board helped me fix it. The thread is this one
. The money quote:
I had the same issue. In my case it was the Samsung Talk or some other such setting on the large main TV where these devices were communicating with each other for power on and off. For instance, when I turned on the front or back TV, it actually was telling the main salon TV to turn on through the HDMI connection. It would just turn on and stay on with a black screen. After 10 minutes or 15 minutes, the large TV would auto shut off for power savings since nothing was playing on it, and that auto shut off would signal all the TVs and BluRay players in the coach to shut off. Boom, power off.
Drive through the menus on your large main TV to find something like Samsung Link and turn that off.
I never had the problem again.