ALSA

To use ALSA, install the alsa-utils package and make sure your user is a member of the audio group.

The alsa-utils package provides the alsa service. When enabled, this service saves and restores the state of ALSA (e.g. volume) at shutdown and boot, respectively.

To allow use of software requiring PulseAudio, install the apulse package. apulse provides part of the PulseAudio interface expected by applications, translating calls to that interface into calls to ALSA. For details about using apulse, consult the project README.

Configuration

The default sound card can be specified via ALSA configuration files or via kernel module options.

To obtain information about the order of loaded sound card modules:

$ cat /proc/asound/modules
 0 snd_hda_intel
 1 snd_hda_intel
 2 snd_usb_audio

To set a different card as the default, edit /etc/asound.conf or the per-user configuration file ~/.asoundrc:

defaults.ctl.card 2; defaults.pcm.card 2;

or specify sound card module order in /etc/modprobe.d/alsa.conf:

options snd_usb_audio index=0

Dmix

The dmix ALSA plugin allows playing sound from multiple sources. dmix is enabled by default for soundcards which do not support hardware mixing. To enable it for digital output, edit /etc/asound.conf:

pcm.dsp {
    type plug
    slave.pcm "dmix"
}