[Elecraft] Squelch

[KJ3D]

Hello Group,
 
I recently installed HSE software and ran into an interesting problem.  The
folks at Callsign Software couldn't provide a solution, so here I am.
 
After the installation, when the K2 was powered up, it would do so with no
audio - but otherwise apparently working fine.  A touch on the key or PTT
switch brought it back to life, but only for 10 seconds).
 
Somehow, the HSE program turned squelch full on on my K2 (ser 4991 with SSB
and DSP).
 
I cannot find a reference to squelch anywhere in the Elecraft literature,
including how to turn it off.
 
I did get it off, but it required installing HRD and installing all the
sliders.  One is for squelch and it was full on.  Turning it off and exiting
the program solved the problem.
 
My question is...
 
What's the story on squelch?  Is there one?  How does one access it -
specifically how do you turn it off if it gets turned on by a third party?
 
TIA,
 
73,
 
Tom, KJ3D