I just wanted to update this thread in case anyone with a similar problem stumbles across it. My rechargeables just died after another month or so and I had the same problem as I reported in my initial post. After fiddling around for a while I stumbled across a solution that appears to work every time. When the remote locks up all I have to do is take the batteries out, put three fresh batteries back in, then hold down "2" while replacing the last battery. No idea why it works, but it does.