Created attachment 876158 [details] aplay in parallel I ran two distinct sounds as: > { aplay -Dplughw:2,0 -vv foo.wav & aplay -Dplughw:2,1 -vv bar.wav & wait; } > aplay_paralell.out 2>&1 The first sound played in stereo. The other, which was longer (didn't know if it would make any difference) didnt play at all and even yield an error. I did run another test replacing one of these by the laptop sound card and heard both sounds (from the different speakers)