My new Samsung 40' LCD TV Displays all movies and tv in 1920 x 1080p and when on a PS3 main menu it is also in 1080p but when i start any game, it switches the tv to 1280 x 720. Why is this happening and how do i fix it because i know i am playing games that support 1080p (Assassins creed 2) and yet it wont play in 1080p