Not your fault. I knew going in that it was about 80% likelihood to fix the problem (based on posts in various TiVo forums) and it looks like I lucked out and got the other 20%.

Weaknees wrote back to me and suggested that I disconnect the IDE cable to the DVD burner and see if that helps; and if not, then they recommend a small UPS that Amazon sells (~$30 incl. shipping) but I wonder if that isn't overkill. I already have a pretty good APC brand surge protecting power strip, and while I know that won't protect against under-voltage situations, in the 14 months I have lived here I have never seen a power failure, nor have the lights ever flickered or dimmed. Power seems to be pretty stable. I'll go ahead and disconnect the DVD and see if that helps, but I'll hold off on the UPS for now.

tanstaafl.