JVC DR-M10 timer rec/channel change problem

[piano632]

Here's a new one for the JVC DR-M10:

Suddenly today I'm having a hard time turning on the timer or changing the channel. Both of these things happened at the same time. I don't know if I accidently hit a button on the remote that might have done something. I am still able to record without the timer and all other functions seem to work as normal. What would cause only the timer rec and the various channel change buttons to become inoperable? I did manage to get both to work for brief periods today which makes it all the more confusing.

[broadway]

maybe weak batteries? just a guess
With my TV remote when the batteries start running low, the channel up/down and volume up/down buttons feel "slow"

[piano632]

Tried changing the batteries - no improvement. Very strange behavior, everything works as normal except anything to do with timer settings or channel changing. Timer won't go on when timer button is pressed. I can change timer settings, but I can't cancel any. I have now resorted to unplugging the machine. Anyone know how long it needs to be unplugged before all the timer settings get wiped out?