[Elecraft] KPA100 audio problem

[Neal Campbell and Sarah Ferrell]

I assembled my kpa100 during the week, what a nice experience!

The functional operation of it is fine, aligned well, tx audio is good, 
temp, etc. all fine.

The problem I am experiencing is with the audio.

If I plug the audio cable only into the k2, audio is as good as the 
original. But if I plug either the 12v line or the rf line, it sounds 
very tinny and distorted. When I  connected the speaker plug from the 
orginal k2 top and then plugged in the 12v and rf line from the kpa100, 
no audio distortion. I assumed I might have wired my speaker backwards, 
but even with both connections free from the kpa100 speaker, it 
distorts whenever I plug in the 12v and/or rf cable. So its something 
on the kpa board itself. The problem is there really is not much in 
terms of audio circuitry on the KPA.

Any ideas?

73 de Neal