[Elecraft] K3 audio problem

[Chris Meagher]

Hi  I have a strange problem with my K3/100.
The audio through the internal speaker is low, but comes up
much stronger with any slight movement of the volume knob.
Then it goes back down again, often accompanied by a brief
HI-CUR warning.
Also when AGC is turned off, audio is almost zero.

But, with the SP3 external speaker plugged in, the problem goes away!
Any insights much appreciated.

Chris
VK2ACD