I've read somewhere that it happens whan the box crashes, I guess it reboots so unless you were present at the time you would never know of the crash but I can't find any solutuions and it's very annoying.
May have to ring VM and have them send a new box out
My V+ box recently announced that the hard disc was full and I was unable to set to pre-record any more programmes. In reality I never seem to use much more than 25% of the drive, even when saving HD programmes. A five minute switch off at the mains plug restored the situation, including the programmes I had previously saved on the disc. I have a feeling that some sequence of events triggers this confusion. No idea what it is, and it has only occoured once in over a year.