External USB Sound Card - No Audio
USB Type A 2.0
USB Type A 3.0
USB Type A 3.1
In Media preferences, I've unmuted every channel and slid all sliders to the positive end.
The input and output frequencies are both showing up as '192000 Hz'
The audio input and output settings both have the single option of 'HD Audio'
I do not understand what the 'isochronous transfers' talked about on the above page are, but it seems that this may be tackled in GSoC 2019 and pertain to external USB sound cards.