On my HR-44 I have had an issue with HD images suddenly stuttering, stumbling, glitching, shaking (probably the best description) and the only way to fix it is to power on/off the unit and it goes away. It seems to happen most often when switching channels from the music 800 channels. I have taken my Denon X-2000 out of the loop, and connected the HR-44 to my Samsung with no change. I have used several HDMI cables (even though I know they are all good) with no change.
I have yet to read any other user on the net complain about this, but last week a user on AVS Forums reported the same issue, with a Sony TV and an Onkyo receiver. Hopefully this update will fix it, as I haven't seen the issue in a few days which is not the norm.