[Elecraft] K3 Monitor feedback

[Mike]

I was playing with ALC and compression settings tonight, and turned on 
the monitor function. If I turn it up high enough to hear myself (around 
9), I get a loud BRRRRRRRRRR squeal, that has an echoic component. 
Difficult to describe.

I don't recall hearing that when I first set up the mic. I have V3.63.

How can I regain use of the monitor?

Mike NF4L

To those who celebrate tomorrow, Happy Thanksgiving.