My problem was within Roon, not the Ultra. At the bottom of the Roon page you’re supposed to pick an audio device. I clicked on it and it gave me two choices. You could choose either ‘system output’ or the second one which had a blank box. I was supposed to type in UltraRendu in the box, but I didn’t know that. I was thrown off by the subtitle below the box which read ‘JRiver’ and some other wording. Once I typed in ‘UltraRendu’ the other misleading wording disappeared. Then the UltraRendu appeared in the selection, I selected it, and music has been playing since.