... I have one HR24-500 (2 months old) that will randomly pixelate for no common reason. Sometimes during live TV, sometimes during playback of shows. When it pixelates during live TV I check other receivers on the same channel and its 100% fine on other receivers. Also, this happens on a random channel. Last night 331 was unwatchable, but other channels I tried were 100%.
I have reset, unplugged, etc. ... I find it hard to believe that heat is an issue.
Anyone have any ideas? Could it be simply a bad receiver?
It could. Probably is. You will probably have to paint a dimmer picture of its performance to CS to get them to replace it, however. But do it soon or you will have to pay the freight as well. Heat is an unlikely culprit, but you can get the internal temp from "settings".
Here is what we know for sure. Pixillation is caused by buffer underflow in the decoder, which implies data is not getting there in a timely manner. Since it is on recordings as well, it is probably downstream of reception, and you can eliminate everything outside the DVR.
Try this: go to (or channel up and down to) a channel without pausing or using trick play. This puts the DVR in a mode where the HDD is not in line (the minute you pause or rewind that ends and the HDD is then on line). If you see random tiling then, this probably eliminates the HDD. All that is left is the decoder itself as a suspect at that point.