I've been struggling to get my USB sound card to work with my Raspberry Pi 3. After following some suggestions I have had limited success. On startup if I run
speaker-test -c2 -twav this test successfully plays off of my USB sound card. However if I use
omxplayer -o local test.mp3 the sound only plays over the headphone jack. The same thing happens in the GUI, if I double-click on an mp3 file, the sound comes out from the headphone jack only.
Anyone have any suggestions?