[Elecraft] K2 Alignment and Testing Part 1 Troubles

[Curt]

I know this list is mainly for K3 owners.  Still notice few postings for K2, 
so am hoping for some help.

I am having a rather vexing time with Alignment & Testing Phase 1.  My 
problem is that all of the front-panel controls and display work as they 
should EXCEPT for the Menu/Edit button.  The button press is making it to 
U2, can see the voltage change on pin 6. All the chip voltage checks seem 
normal.  I have performed the master reset operation, it proceeds as 
expected but doesn't fix the problem.  One additional behavior noted is that 
if the K2 rests overnight without power connected, then the Menu button is 
pushed immediately after power-up and initialization is completed ( 7.100 c 
on display ), the st L 40 appears.  Usually this will only work once or 
twice,  thereafter it stops working.  Elecraft is sending a new MCU, but 
somehow I suspect this isn't the problem because everything else seems to be 
working so well.

Has anyone else experienced this problem, or does anyone have advice about 
how to determine the root cause of the problem ?

73, Curt KB5JO