The bug on the 721 where if you are viewing a A/V input on Channel 0 for a while and it distorts where it looks mostly black and white and has lines and the audio is distorted as well. I used to have to flip the channel up then back down but I discovered a better way of getting through the bug without having to do that. Just hit the PVR button and you will notice in the PIP screen that it returns back to normal. Hit PIP then cancel and its back to normal. It is a lot quicker than changing the channel then having to hit 0 again.
