I get this exact same thing with my Motorola cable box, but it only
occurs on certain channels some of the time. For example, during
the NFL season, I was flipping back and forth between two games and it
was happening on one channel, and not the other. My opinion, and
it is only an opinion, is that the cable company compresses some of the
channels to save on space or bandwith(?) and that's why the pixelation
is happening during fast-moving scenes. Maybe DirectTV does the
same thing. Anyone else care to jump in?!?! I have been
wondering about this for a while.