Thank you for the tips. It actually was a dead battery; as soon as I plugged it in, it rebooted and worked! This is the first time this has happened, and I believe happened because the wife was (still is, a bit) sick and was spending time on the couch. Several days of watching TV and using the remote apparently wore out the batteries. Usually, we watch a little TV in the morning and a bit at night, and then use the remote for listening to music. It doesn't need a charge for many days that way.

I have to say that I freaked out without this remote. First, all my gear is hidden behind a chair and I'm using wireless. All the IR sensors for the gear are taped over. I had to dig out the 5+ remotes necessary to run the system, and then they were basically useless since the gear is hidden.