From the sounds of it, your box is rebooting after every guide update then.. or failing. I'd think this is indicative of either a failing box, or maybe (unlikely but possible) something a bit amiss in the guide data/scheduled programmes.
I can't check at the moment, but there's an option somewhere in the help & settings menu for "delete planned recordings and reboot box" or similar. You could try this on the off-chance some programme scheduling is causing a problem... but I have my doubts.
You're probably going to end up calling this in as a faulty box I suspect.