find / -iname '*.mp3' -exec /home/peter/Downloads/mp3gain/mp3gain -r -c -m 4 {} \;
Control the volume using the alsa utils.
The volume of sound cards can be controlled with amixer.
amixer set -c 0 Master 25 unmute amixer set -c 0 PCM 25 unmute
alsamixer
Save the settings.
sudo alsactl store
amixer set Master playback 5dB+ pactl set-sink-volume @DEFAULT_SINK@ +5%
amixer set Master playback 5dB- pactl set-sink-volume @DEFAULT_SINK@ -5%
amixer -D pulse set Master toggle