I recently bought a Samsung 56" DLP (HLN567W). I also have a Comcast HDTV tuner (I think it's made my Motorola). I started by connecting the Comcast box to the DLP using componant video (green, blue, red). This is fine for watching HDTV channels, but when I switch to a non-HDTV channel, the TV screen goes blue and says, "Not Supported Mode." So, in addition to the componant video, I have now added a second connection - just the basic coax connecting the cable box to the post on the back of the DLP. This solves the problem, but it's annoying because I have to switch AV modes on the TV every time I switch back and forth from HDTV channels to regular channels. Why can't I watch both HDTV and regular TV through the same video connection? I used to be able to do this on my 32" Sony HDTV (4:3).