[Elecraft] KX1 Q: Processor won't reset? Rig confused. Why?

[B. Scott Andersen]

I have a KX1 that has worked flawlessly until now.
(Just got my 1000 miles/watt award. Cool!)
I run it off batteries and listen to it at night before bed. I fell 
asleep and
forgot to turn it off. A day later, I discovered it just sitting there 
with
very nearly dead batteries and the left-most LED blinking.

It now has new batteries but it has become nonfunctional.

Symptoms:
1. Processor will not reset as per manual.
    I hold down the BAND+MENU buttons at power up but the LEDs stay dark.
    I never get the "E9" or "E10".
2. It appears as though the "Dah" paddle is depressed, though no
    paddles or key are connected. Putting paddles in and pressing
    "Dit" will do the iambic thing.
3. BAT LO will occasionally pop-up after power up.

I am confused because:
1. Nothing physically happened to the box except it sat there until the
    battery ran down. Why would it now act like the "Dah" paddle was 
pushed?
2. Why can I not reset the processor?
3. Batteries are new. What's with the BAT LO thing?

Things I've tried:
1. Disconnected the ATU.
2. Disconnected all power for a while, hoping to get the processor to 
behave.
3. Applying external power (not just AA cells in the belly of the 
beast).
4. Disassembling the unit completely (except for 30m board) to see if 
there
    was a problem visually.
5. Tried applying power with the unit out of the aluminum case. No 
change.
6. Resetting the processor repeatedly, without luck.
7. Version number check (any switch on power up) DOES work. Version=101

It is time for me to put it on the bench and start checking voltages.
But, I fear that the processor has somehow lost its mind. Has anybody
seen anything like this? Is there anything I'm missing?

Sorry for the long note. I will, of course, let the list know what
was done to resolve this once I get the little gem back on its feet.
Thanks. 73!

-- Scott

B. Scott Andersen    | "Magic is real, unless declared integer."
bsandersen at mac.com   | -- The collected sayings of Wiz Zumwalt
Acton, Massachusetts | Ham: NE1RD, QRP ARCI#11588, FP#-910