For the last 3 or 4 months (started prior to HD GUI release), I'll come downstairs for my evening walk on my treadmill and my HR21 is totally unresponsive. I usually get down there before The Office finishes recording, so the recording light is on, but I can't get the HR21 to respond to the remote or the power button on the front panel. No choice but to give it the old red button reboot. Happens at least twice a month. Happened three weeks in a row in Jan. Happens only on Thursdays. Crazy. My HR20 works fine. What is going on?