How to change the default sound card in Ubuntu
Wed 18 Jun 2008
If you have installed a second sound card into your computer you may find your onboard sound card is still the default, even if you have disabled the onboard in the bios.
Identify the problem
cat /proc/asound/cards
0 [SB]: HDA-Intel - HDA ATI SB
HDA ATI SB at 0xfebf8000 irq 18
1 [CA0106]: CA0106 - CA0106
Audigy SE [SB0570] at 0x8c00 irq 20
As you can see the onboard ATI/AMD sound card is card 0 and the Audigy SE card is card 1
Identify the modules
cat /proc/asound/modules
0 snd_hda_intel
1 snd-ca0106
So snd_hda_intel is the onboard, snd-ca0106 is the Audigy
Method 1, Disable onboard
echo 'blacklist snd_hda_intel' | sudo tee -a /etc/modprobe.d/blacklist
This will prevent the snd_hda_intel driver from loading on boot
Method 2, Swap the default sound card
echo -e 'options snd-ca0106 index=0/noptions snd_hda_intel index=1' | sudo tee -a /etc/modprobe.d/alsa-base
Reboot and test
check cat /proc/asound/cards to see if Audigy SE is now card 0 and test the sound
