TV Lousy Picture

I have a 2007 3124KB that came with a built in TV and DVD player. The picture has been watchable but hardly great. With DVDs it has a tendency to have a pinkish cast to it and now with a satallite dish (roof antenna is worthless in most places we go) it has lines and or a reduced screen size. I have tried every adjustment to the picture that I can think of with no help and am reaching the conclusion it has to do with the DVD to TV setup. Since this is not a common factory install ,according to the dealer, they basically don't have a clue. Any similar problems or ideas out there?