Originally Posted by AMMO
Yes, I have noticed same, but not sure of channels, also in sammamish.
I had a tech come out last Thursday afternoon and, of course, there was absolutely no pixellation going at that time. He checked my signal strength etc. and told me that the problem was probably at Comcast's end. I DVR'd Gray's Anatomy Thursday night and of course the pixellation had come back. I have continued to have off-and-on issues since then.
The tech told me that we should call in any pixellation issues as the problem may be at Comcast's end and fixable, if only Comcast knows about it. Sometimes problems go unreported and thus unfixed for a long time.
The other thing he told me is that if you go to the inband diagnostics (turn off the cable box, press OK/Select on the remote, and then choose inband from the menu that comes up) you can make a pretty good guess as to whether the trouble is at your end or at Comcast's end. If the diagnostics show that signal-to-noise ratio is good, but that there are a lot of "uncorrectable errors" that is a sign that you have a good, strong signal, but that Comcast is passing you a bad signal that has errors (i.e. the problem is at the head end or node). If your signal-to-noise ratio is poor, your problem is local to your house.