TheaterWide 16x9 Rear Projection? Don't those Wide Screen nows days digitally zoom stratch pictures to fit on screen? Try using 4:3 mode and see if the quality improve?
Yeah, I seen a lot of those. One customer had a old wood 27" Zenith TV when I put DirecTV for him picture look great on it, then he upgraded to a 36" Sony and you can definitely see the Picture quality changed. Went back to his house for Service call about his PQ so I helped him put the TV side by side and what a different. On the new Sony you can see all the digital artifacts and colors are all washed out, especially on the local channels. On the old TV pictures was superb.
I have seen older sharp LCD can't handle DirecTV compression, some Sony WEGA, Sony CRT Rear Projections, Toshiba Wide Screen, Samgsung DLP, some Pioneer Plasma that look like crap no matter what connection you use.