Occasionally I will see small squares over part of the screen for a few seconds while watching HD. At first I thought it was signal breakup but I've set up my 622 and 942 to the same program and the boxes only appear on the 622. Has anyone else been experiencing this? Not sure if the 622 is just more sensitive to signal strength or what the cause is. It is more of an annoyance than a real problem, picture returns to normal after a few seconds. While I've seen it more frequently off the 129, I've also seen it on channels off the 110. Have not seen it happen on OTA channels. And it doesn't seem to happen to SD programing.