[Elecraft] K2 doesn't work with mic connected

[Gary Krause]

I thought I had a problem with the control board originally.  When I 
turned on the K2 the "Elecraft" would come up and then go to the 
frequency.  However, everything was frozen.  Nothing worked and the 
frequency couldn't be changed.  I re-installed the control board, turned 
it on and everything worked fine until I plugged in the mic.  Then 
everything froze again.  Unplug the mic and everything comes back to 
life.   I checked the jumpers for my mic configuration and they are 
correct.  I'm using a Kenwood MC-60 mic with an internal preamp.  
However, I don't use the preamp but, I have the jumper installed for 
it.  Any ideas?

Thanks,
Gary, N7HTS