[Elecraft] K3: No Audio into FP or RP Mic?

[Eric Fitzgerald]

This will probably end up qualifying for the lamest question ever asked but I would really like to get on the air for IARU.

I just set up my K3 in a new location after Field Day and I've been working the digital modes no problem.  I switched over to USB on 20m this morning and plugged in my Heil ProSet and... no audio into the K3.  I checked the obvious - mic gain, monitor gain, connections, etc but no joy - I cannot budge the ACL meter and nothing heard in my monitor.  PTT is working just no audio into the radio.  I even tried a different mic into the front panel jack (Obviously switching to the front panel input) and same result, no audio.

I double checked that the Line In is still delivering audio and it is.  Just nothing via the mic inputs.

Any ideas about what stupid thing I'm doing?

TIA

73 de Eric, KG6MZS