I'm getting pixellation/breakup, but only on certain channels when using SAT 2 input.

All channels on SAT 1 are fine, so I'm thinking that rules out the hard disk.

Almost all of the channels on SAT 2 are OK, with a just a few prime exceptions of CNN, ESPN and a few others. Those show pixellation and breakup, sometimes severe, sometimes just minor.

I've swapped cables and checked my multiswitch, the problem stays on SAT 2, so I'm thinking that rules out cabling.

Would this be a bad tuner, and if so, can I do anything about it? I mean, besides running setup again and telling it I have a single LNB or locking out the bad channels. I know I can do that, but really saving that as a last resort.

Any help welcome! I did upgrade the disk in this unit about 6 months ago, but that upgrade went fine. It's only been pulling this pixellation trick for the last month or so. I had thought it was just cabling so I was waiting for a good time to go up into the attic to fix it, but no luck, all the cables are nice and tight.