[Elecraft] K3 - Erratic receive

[Pete Smith N4ZR]

My 2400-serial number K3 has begun to have a sporadic receive problem, 
which has gotten much worse recently.  It's really weird.

What happens is this - the receiver sporadically loses most of its audio 
output level, until I move the AF pot a couple of degrees either way, at 
which point it immediately restores the audio.  Often, but not always, 
this occurs right after a transmission (on CW), so I was initially 
suspecting a failing relay, but the way it responds to a minute change 
in the AF level setting makes me think something subtler.  Any ideas?

-- 
73, Pete N4ZR