Cable Software Change and IR Channel Change Problems

Our cable company recently changed from Passport Echo to iGuide software. Ever since then, the Series 2 Tivo we have in the bedroom has a miserable time getting the right channel set on scheduled recordings. It was rock solid before the change. Changing the channel while watching live TV works fine.

I've run the channel changing setup multiple times, trying various different options. It will tend to work so-so for a while then degrade over time.

Is it a coincidence and my old Tivo is giving up the ghost after all these years? If that's probably not the issue, does anyone have any helpful hints for me to solve the problem?