(Q1002USB, USB out to Win 10 computer running Audacity.) It records from the desk fine. When I play back a track from Audacity, I can monitor either the recorded tracks, when I push the USB/2 Track to Phones/CTRL RM button; or the live playing through an input channel, when that button is not pushed. I see from Audacity that the desk sends the live input to the computer even when the button is down.

How do I monitor both so that I can overdub?