Finally got a TivoHD working with a cable card, and am now playing with it a bit. From the Now Playing list, I pressed Enter to change options, and turned off Groups to see what that would look like. As soon as I chose the option to save the changes, the unit immediately rebooted. Of course I didn't think that was normal, and after it came back up I turned Groups back on, then turned them off again but the reboot didn't happen a second time. So my question is - is the TivoHD going to spontaneously reboot like that occasionally, or should I be worried that this happened?