When a favorites list or All HD is active and you are tuned to a channel that is NOT in that favorite list when you power off you will be defaulted to 101 when you power on. This also happens when you are tuned to a channel not listed and return from watching a recording. Been happening at my house for a while because I set the favorites list to All HD and the wife watches QVC - which as we all know is not HD yet - to go to sleep. In the AM it's 101 again.
HTH,
Jeff