I bought a couple of Series 3 TiVos when they first came out (and naturally upgraded their hard drives using Weaknees). They have been a pleasure to use. Recently one of them has started to experience large blocky streaks on some channels. Both S3 machines (and a bunch of others) are hooked up to a Channel Vision 8-port RF distribution amp, and use CableCards.

I checked the signal strength meter on the two and the failing one is between 45-60. Some HD channels are showing as 0 however, and some work but claim the second tuner has no signal. On the working S3 box almost all channels are in the 90s. I have tried different RF cables and although there are some small differences nothing seems to fix it. This is a recent problem, the affected S3 has performed admirably until now.

Has anyone encountered this failure mode before?