I have a Sony SVR 2000 and starting a month or so ago the picture would freeze and/or pixellate, and the sound would drop out for about 5-8 seconds. This happened fairly consistently despite recording quality (though it did seem worse recording at lower quality). The effect even happens when watching live TV through the TiVo. It will happen at least once during a 1/2 hour show.
Research showed that it was probably a failing hard drive so I got a new one from PTV. Installation went just fine, the machine booted, recognized my subscription and loaded the schedule. It showed my new larger recording capacity.
HOWEVER, the problem persists exactly as before. What else could it be? The temperature shows 33°c (Normal) and I do not have a cable box; the cable seems secure and goes right into the TiVo.