I had to remove the following default line from
/boot/config.txt:
dtparam=audio=on
/boot/config.txt, and rebooted:
I confirmed the DAC was working correctly by running
sudo aplay -l.
mplayer (e.g.
mplayer file.mp3).
I should note that by default, using my pair of Audio Technica over-the-ear headphones, I was glad to not have them on my ears when I did this the first time—the default volume was something like 88%, and that would've probably ruptured my eardrums!
I turned the volume down to a more pleasant 4% using the
/ key and was able to enjoy a few songs through the MirkoPC. The audio circuit on it sounds great, and I could not hear any discernible background noise—which is better than I can say for many devices!