Twice in the last couple of weeks my HR21-700 has rebooted on its own. On several other occasions including today it has stopped reacting to any commands either via remote or directly on the receiver. In a couple of instances the "freeze-up" has occurred with the unit on. The only way I knew something was wrong was when I couldn't change the channel. Today and also the other day when I went to turn the unit on, it wouldn't turn on -- even when pushing the power button directly on the unit. I had to push the reset button both time to get it to come to life but of course had to go through the complete cycle including downloading from the satellite. This particular unit is hooked to an external hard drive which remains on all the time so I'm assuming that cannot be part of the problem. Should I try forcing a download (02468)? If I have to have to unit replaced I would lose all of the recordings that I have stored.