This is a list of the order of the sound modules loaded by alsa currently:
snd_intel8x0
snd_usb_audio
The sound modules are for these cards:
snd_intel8x0 "ICH - SiS SI7012"
snd_usb_audio "USB-Audio - Logitech USB Headset"
You can reorder the loading of these modules for your needs:
Close all sound apps,daemons,mixers,
and mixer-applets like kamix and gnome-mixer;
If you can not close these sound apps you may have to
logout from your window manager and login to a new
console using ctrl-alt-F2; then try this command
which will attempt to kill all sound apps,mixers,daemons,applets:
as root: kill $(lsof -t /dev/dsp* /dev/audio* /dev/mixer* /dev/snd/*)
run this command to see which sound apps are using your card now:
lsof /dev/dsp* /dev/snd/*
When all sound apps are closed then reload your sound modules by
running these commands in the order printed below:
modprobe -r snd_usb_audio
modprobe -r snd_intel8x0
modprobe snd_usb_audio
modprobe snd_intel8x0
If the modules load ok manually you may want to edit one of these files
to load the modules in the NEW order on each reboot:
edit /etc/modprobe.conf OR /etc/modprobe.d/ for debian/ubuntu based distros
to change default card order.
Add these lines to the End of the File listed above:
options snd_intel8x0 index=-1
options snd_usb_audio index=0
If these commands do NOT load the sound modules in the correct order then
remove the lines you added from the file you edited. There is another method to try.
Copy/paste this script to a file in some secure directory like /root:
#Begin file to save (Don't save this line)
#!/bin/sh
modprobe -r snd_usb_audio
modprobe -r snd_intel8x0
modprobe snd_usb_audio
modprobe snd_intel8x0
#End file to save (Don't save this line)
Edit /etc/rc.local and add a line to run the "file to save" on reboot.
If running this file from /etc/rc.local does not work properly then edit
/etc/rc.local and remove the line that runs the "file to save" on reboot.
Contact the alsa developer for the linux distribution you are using
to ask how to change the default sound card order on reboot.
memo gnubien at freenode.net to inform me of which /etc/file works
to load the sound modules in the correct order and the linux
distribution and version you are using; improvements and additions
to this script are welcome also.