No signal on 101

So, I came downstairs this morning and my HR20 was on a frozen, distorted picture. Figured it locked up, did a reboot and went to work. Came back and it was stuck on acquiring guide data. Did it again, same thing. Checked signals and was getting almost nothing on 101, not zeros across the board, but pretty much. Checked signal strength, it would go between 0 and 32% (or so). Other sats appear fine. Tried removing the b-band converters, no change. Unplugged the reciever for 30 min, same thing.

So, best guess, is this:
a.) a dish alignment problem
b.) a multiswitch problem
c.) a box problem
d.) anything else?

I'm willing to get on the roof and make an adjustment, or call D* if necessary, I'd just like some educated guesses on what the problem might be. Right now, I'm pretty much screwed on that box since the guide data must DL from 101 and I can't get past that screen.

Thanks.