My hard drive is in the process of slowly dying. I intend to replace it soon. I get freezing, pixelation, occasional reboots, lack of responsiveness to remote commands, etc. Many people, including myself, have gotten temporary relief from these symptoms by restarting the TiVo. I was curious as to why and I had a theory. What if it isn't the restarting of the TiVo that alleviates the symptoms, but the clearing out of the cache/buffer? I tested this and have found that with my TiVo at least, if I have problems, I can go to live TV, change the channels (thus clearing the cache), and suddenly my symptoms are gone, for several minutes at least. I suspect that rather than storing the cache/buffer in RAM, that it is stored on the hard drive. Maybe there is some other explanation. I know it isn't a cure, but for people in my position, who are trying to get by while waiting to fix the problem, it could be a handy piece of information.