Advertisements This sounds like something I have been trying to get Tivo to fix with both of my HD tivo Boxes. Both HD tivo were purchased a year apart. Both Tivo will drop all Large blocks of channels at any time. The channels lost mostly are analog. I have called Tivo many time to see if they knew what the problem was. They finally told me this is a known problem that almost all the HD tivos have. They have been working on a fix, but that have nothing at this time. I asked for a discount until they resolve the issue. They said there was nothing they could do because the problem affects all the HD Tivos at one time or another. They also said they had no idea on how long it would take to fix the problem. It would be interesting to know how many HD owners Tivo's drop blocks of channels for a day or so and then get them back? What can I say. Misery loves company.