XT3 Getting multiple keystrokes

Having somewhat of a unique problem.  I have an XT3 tablet and an issue arose from the blue that when the user tried keying in the system password, the first key pressed would generate multiple, infinite keystrokes.  The kicker is that it only happens during post, and will work ok with an external keyboard.  Once loaded into Windows, the internal keyboard works fine.

I have updated the BIOS, replaced the keyboard and ultimately replaced the system booard but the problem persists!

Scratching my head at this point.  Any suggestions would be most helpful and appreciated!

Thanks!