Petar, I am using the D&R Airlite exactly the way you plan. Works like a charm. For you, next step is to assign the correct “Line” output to the Encoder.
"line"is the output on which the Master Signal of the D&R Airlite is connected. To identify, go to the Windows Mixer Section. Check which USB channel is “Line”. See attached picture. Choose this Line as input for the Encoder.

