-# Use ALSA as audio driver, use PCM for volume control.
-ao=alsa:mixer-name=PCM
-# Use the audio driver volume control if possible.
-softvol=no
+# Use ALSA as audio driver.
+ao=alsa
+# Set default value of internal mixer (0-100). Since 0.18.1 mpv has no access
+# to hardware mixer.
+volume=50