How do I choose which soundcard ALSA uses?

Question

Hello I am having a problem that ALSA uses the wrong soundcard, does alsa-utils or any others package provide a tool which I can make ALSA use the right soundcard?

Answer 1

I spent weeks trying to find the best solution to this problem, and it's very simple. 
Just put this in your .asoundrc:
defaults.pcm.card 0
defaults.ctl.card 0
Change the number to whatever you want, and you can find them out with "aplay -l".  And only use numbers.
Using this method, you can change the default sound card on a per-user basis, after boot time, without having to edit anything as root.
I wrote a script that can do it for you, and handles volume control too:
#!/bin/sh
config=~/.asoundrc
choose () {
echo Choose a card:
aplay -l
read card
echo Choose a control:
amixer -c $card scontrols
read control
echo "#" $control > $config
echo defaults.pcm.card $card >> $config
echo defaults.ctl.card $card >> $config
control=(`cat .asoundrc`)
control=${control[1]}
case $1 in
up) amixer -q set $control 5%+ ;;
down) amixer -q set $control 5%- ;;
mute) amixer -q set $control toggle ;;
*) choose ;;
esac
Last edited by Odysseus (2009-04-28 20:58:47)