Both of my Series 2 TIVO units have recently started to take it upon themselves to reboot without any action on my part. On a frequency of perhaps once a day or on occasion once every 2-3 days, they will, within a minute or two of turning the TV on, go from being on standby to performing a system reboot. The only change that I have made to the setup is the addition of a digital cable box that gets its signal from the wall outlet and inputs its output to the TIVO unit. The TV gets its input from the TIVO. The cable box must be on for any signal to get to the TV. I'd appreciate any help in getting rid of this annoying action.