[NTLK] Dying, now dead 2100

I've got a MP 2000 upgraded to 2100. Bought it late fall.
It has worked well until a couple of weeks ago. I was unplugging the AC
power cord, there was a small spark between hand and MP and it went
dead. About 15 minutes later, after pressing the reset button a few
times and attempting a brain wipe, it came back on, started up and
worked fine.
Awhile later it did the same thing, this time on inserting a Bluetooth
radio card. Locked up. Sat awhile and then started again, this time
after only a reset.
Today it died again, again on card insertion, and there's no restarting.
I've resigned myself to having to buy a new one and will probably call
J&K to see what's what. (Anyone know the difference between their $155
and $129 models, except the more expensive model comes with the lid?)
But me being me, I'll probably take the 2100 apart to see what I might
find inside. Can anyone suggest where I might start in diagnosing/fixing
what's gone wrong?
There's no screen activity, no sound: nothing. Power is good. I've tried
both AC and fresh batteries.
Any suggestions are much appreciated.

ST

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