You can test it with it: Code: # Left speaker On, Right speaker Off amixer -D hw:0 set PCM 100%,0 # Left speaker Off, Right speaker On amixer -D hw:0 set PCM 0%,100% Also you can run alsamixer -c0 and change volume on 'PCM' for each speaker independent with shortcuts: Q,Z - left speaker volume W,X - both volume (same as arrows keypad) E,C - right speaker volume
# Left speaker On, Right speaker Off amixer -D hw:0 set PCM 100%,0 # Left speaker Off, Right speaker On amixer -D hw:0 set PCM 0%,100%