Thanks Will for responding and for your suggestion.
Just to be sure:
- Are you talking about the jumper on the PCB, just below the USB connector? (See picture, left red circle)
- For the ‘AGND’ pin, I believe you mean the 2nd pin from the left in the 4-pin connector just below the green connector block for 5v input? (See picture, right red circle)
So if I get it right, you mean to take the jumper out, and connect the AGND pin?
I did try this situation, taking out the jumper and using the AGND-pin of the 4-pin audio-out connector. In my case I did not notice any difference.
But maybe I got your suggestion wrong? Please let me know.