A few days ago, just before the sofware update was coming down, I had the recorder set to record 2 programs at the same time. When I turned the receiver on to check the recordings, the screen showed all gray on both tuners. I tried to play the partial recording, but it also was gray. I checked those 2 channels on another dvr and both were showing normally, but they did not show up on the HR21 until AFTER I stopped recording. After that, everything was normal.

Yesterday, the same thing occurred again, except this time I could not stop the recording of the gray screen and had to reboot in order to regain control of the receiver. Has operated normally again since then.

I have 2 standard def DirecTivo units and 1 standard Directv dvr also hooked to the same dish, and the problem has not shown up on any of those.