[yunlin12]

and the SW update introduced a new issue (grey screen for a few secs when changing channels).

Did you check your output resolution again? native? 1080i/720p fixed or hybrid? Sometimes that setting gets changed after a reboot, and if it's changing resolutions, maybe there is additional handshake with your TV.

 

[yunlin12]

Wow, I have been weighing numerous options w/ regards to my Series 2 TiVos, including staying put, upgrading to one of these new Tivo HD boxes or stopping TiVo completely. I am extremely glad I found this thread, so I can drop that upgrade option from consideration!

Any possibility they (TiVo) just cheaped out on the video output hardware; e.g. used an underpowered video chipset for what they're asking it to do?

Not like a video output HW since it should not be related to specific cable card slot, it's probably related to the tuner: ATI Theater 314 demodulator chips for digital cable or ATSC signals, which may be impacted by bad signal on cable cards. Some people also reports that OTA without cable cards is also impacted. Don't know why that happens, it could be that the ATI chip is not as reliable or mature. According to Megazone's review, this choice of ATI chip is a cost choice:

http://www.tivolovers.com/a-review-of-the-tivo-hd-digital-media-recorder/