[Elecraft] Strange K3 microphone /PTT fault

[Lyle Johnson]

If Pins 7 and 8 are connected together (verify with ohm meter) but not 
connected to the mic jack shell, you may wish to remove the front panel 
assembly and look just above the Mic Jack at a component labeled "L4".  
It should be a short.  If it is broken, or other than a short, replace 
it with a short length of wire to jumper it, or otherwise jumper pins 7 
and 8 to ground nearby.

K3 product produced starting sometime in 2012 did not have this 
component; earlier ones did and required the jumper.

73,

Lyle KK7P

...
I can operate the PTT on the back socket of the rig, and by grounding
pin 2 on the 8 pin mic connector.

On measuring the pins 7 & 8, which should go to ground, these seem to be
floating and not grounded.

I've just looked at the circuit and it shows these pins going to ground.

Any suggestions?