Korg Poly800/EX800 Users

Hey... I'm a new guy.  For starters, I have to give full props to you
lot for the *outstanding* work you're doing in the revitalization of
the Poly 800.  Really, it's a damned amazing community ya have here.

Anyway... I fished a reverse key mk1 out of a dumpster last night; 
took it home, stripped it down, cleaned the remains of what appeared
to be a burrito off of the keys, keybed and main board, vacuumed out
the case and blew the boards off with compressed air. Metered the
onboard battery at 3.23 volts, then put it back together, slotted 6 C
Cells and fired it up.  Up comes 11-p, and it outputs *some* kinda
sound... sinish, with swept noise... could be a glitch, coulda been
intentionally programmed.  20 seconds later the second digit of the
display goes blank, the first digit dims to 50%, and the controls lock
up.  

Tried the fire up procedure a few more times, learning that there's
nothing audible from any of the other patches, but the lock-up occurs
every time 18-20 seconds after power on.

Damn.

Any suggestions?

Kaden