/etc/asound.conf
file. pcm.hifiberry {
type softvol
slave.pcm "plughw:0"
control.name "Master"
control.card 0
}
and optionally
pcm.!default {
type plug
slave.pcm "hifiberry"
}
Then use newly defined hifiberry output device:
speaker-test -D hifiberry -c 2
and see new 'Master' control in mixer:
alsamixer
Modify also configuration of your player to use hifiberry playback device. If you use mpd
/etc/mpd.conf
file should be modified in audio_output section:audio_output {
enabled "yes"
type "alsa"
name "HiFiBerry DAC+ Lite"
device "hifiberry"
auto_resample "no"
auto_channels "no"
auto_format "no"
dop "no"
}
For more details see How to use softvol to control the master volume and A close look at ALSA.