This is an "out of curiosity" question. I have multiple backups of this unit,
and //do not// intend to repair it. I just want to see if anyone has any
interesting insights.

The unit is a D-FJ75TR, one of Sony's last "deluxe" Discmans. I'd been using
it to listen to CDs in bed, and yesterday it stopped working correctly.

When I install the batteries, or plug it into the adapter, it immediately
starts to play -- and none of the controls work. I can't pause it, change the
track, set the volume, etc. Nor do any of the controls on the remote/tuner
module work. (Unplugging the remote doesn't fix the problem. And the control
lock button isn't jammed.)

The "obvious" answer is CMOS lockup, which I've seen on other products.
Yanking the power while the device is running sometimes cures this, but not in
this case.

I'm not trying to start an extended, overwrought discussion. I'm just
wondering if anyone has any ideas.

Thanks.