[CQ-Contest] Remote, Elecraft K3, Mumble, PC, Anydesk - audio configuration help needed

[w5wz at w5wz.com]

I'm working toward the remote operation of my station.  I have my Mumble 
server working, with a channel for each radio.  At each operating 
position,  I connect the radio to the PC, and on that PC connect to 
Mumble as Rig-x, and enter the channel Rig-x.

Remotely, I connect to the PC for Rig-x via Anydesk, and also connect to 
Mumble as W5WZ and enter the channel for Rig-x.  I can hear the received 
audio from the receiver on the Mumble channel.  With vox enabled on my 
K3, my spoken audio from the remote location via the Mumble channel does 
properly key the transmitter.

BUT, the problem I am having is that my remotely spoken audio, while the 
transmitter is keyed, is coming back into my ears via the Mumble channel 
(causing me to babble!).  Monitor function on the K3 is turned off.

I feel like I'm missing something very simple.

Does anyone have any thoughts?

--Scott, W5WZ