Yes good point John
With this ''not selected'' it's not possible to route audio from a app running on
say sdr & fire fox to data app , vara , fldigi etc using the internal audio routing
Selecting , allows the windows mixer to be selected as audio in
Then there is a listen to this device option, which if activated caused [on my] win10 set up
something like a ' wem copicat' effect , loop round delayed audio
feed back ..all for free ..
Applicable to System audio , as opposed to device audio -?