Hello. Sorry I don't know if this is old hat but we are getting quite a lot of pixelating, freezing for a few seconds and jumping, both on recordings and live (the recordings, of course, were from live!). I've just tried the online test thingy and switched our Tivo off and on again so it might have cured it though I did this a few weeks back and no change. It happens a few times every evening.
Everything seems slow to respond as well, which is probably not related to this, but the pixelation, freezing and then jumping is tending to spoil viewing.