I have two Tivos: a Tivo HD and a Tivo Series2. The problem I'm having is only with the Tivo HD. I'll turn on the TV and either find the picture frozen or the screen will be black. A check of the History reveals that certain shows were not recorded because of a "lost signal". Changing the channel several times seems to bring it back, but this keeps happening with increasing frequency. I don't have a problem with the other Tivo. I have standard cable. No external hard drives. No CableCARD. I don't know what to check or try to resolve this problem. I've only had this Tivo for a couple of months. The problem cropped up after just a few weeks.