Blotchy video issues on only some channels

For the last couple weeks, we've been having signal issues on some channels. Sometimes we just hear the audio skip a few words. Other times, the video gets totally blotchy/tiled for a short period of time and sometimes the scrambled video lasts for several minutes. I have two Tivos, a Premier XL and a Bolt hooked up to Comcast cable via cable cards and both show the issue, though if I'm recording the same show on both Tivos, I don't always see the same issue at exactly the same point in...

Blotchy video issues on only some channels

Blotchy video issues on only some channels