I got Tivo last night and am having problems getting RGB. when i select AUX on the remote my tv switches to RGB but if i playback anything from Tivo it switches back to composite. as soon as i press the tivo button to go into the menu it switches back to composite, is this correct??? i have chosen RGB in all the settings, the cables are ok , because i get RGB from sky when i choose AUX. if i press the thumbs up button it switches back to composite too. is it meant to do this ???