My Dad's Tivo was crazy, despite him recording a lot of stuff on CNBC and watching mostly the History channel, it insisted on recording stuff on Arabic satallite stations that we don't even get. It'd literally fill up the drive with recordings of Al-Jezerra and all that would be on there was "This is a channel you do not subscribe to, please call customer service to have it added".
He finally turned off the auto-record thing and it's better now. It was pretty funny at the time though.