I hope you won't mind me stepping in - I'm sure Carl can defend himself - but he does raise a valid point, because I don't have this issue either, and more to the point Spiderplant has made it pretty clear that what you're describing shouldn't be happening. If it is (and I'm not for a second disputing what your saying) then perhaps you have a problem with your box and should ask Virgin to send somebody to sort it out?
As for the comments about Carl, I'm sure he'd acknowledge problems with the Virgin network, but he'd let you know the TiVo itself was still working fine