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bpont

Banned

Registered: 2010-03-24

Posts: 161

ALSA configuration files are not working

I'm having configuration issues with ALSA.  I consulted the Wiki and created a file with the following settings:

/etc/modprobe.d/alsa-base.config

options snd slots=snd_emu10k1,snd_ac97_codec
options snd_emu10k1 index=0 
options snd_ac97_codec index=1
# Keep snd-pcsp from being loaded as first soundcard
options snd-pcsp index=-2
# Keep snd-usb-audio from beeing loaded as first soundcard
options snd-usb-audio index=-2

I disabled my previous configuration file /etc/modprobe.d/sound.conf and rebooted.  The boot messages scrolled too fast, but I saw some error about "index" not being an option.  No sound driver was loaded.  Attempting to run 'alsamixer' returned 'file not found.'  Consequently, I re-enabled /etc/modprobe.d/sound.conf and rebooted, but no sound driver was loaded and I still couldn't run 'alsamixer.'  It wasn't until I disabled /etc/modprobe.d/alsa-base.config and rebooted that alsamixer worked again and a sound driver was loaded...sometimes a reboot randomly loads usb device (which I don't want) and sometimes sb audigy (which I do want).

What is the correct way to ensure that my preferred sound card gets loaded first on every boot and that the usb device never does?  The wiki seems to be outdated.

By the way, here's my /etc/modprobe.d/sound.conf

alias snd-card-0 snd-emu10k1
alias sound-slot-0 snd-emu10k1

brebs

Member

Registered: 2007-04-03

Posts: 3,742

Re: ALSA configuration files are not working

My /usr/src/linux/Documentation/sound/alsa/ALSA-Configuration.txt (from kernel 3.4.38) says:

    index   - index (slot #) of sound card
        - Values: 0 through 31 or negative
        - If nonnegative, assign that index number
                - if negative, interpret as a bitmask of permissible
          indices; the first free permitted index is assigned
        - Default: -1

bpont

Banned

Registered: 2010-03-24

Posts: 161

Re: ALSA configuration files are not working

My /usr/src/linux/Documentation/sound/alsa/ALSA-Configuration.txt (from kernel 3.4.38) says:

    index   - index (slot #) of sound card
        - Values: 0 through 31 or negative
        - If nonnegative, assign that index number
                - if negative, interpret as a bitmask of permissible
          indices; the first free permitted index is assigned
        - Default: -1

Thanks, but it doesn't indicate any obvious errors on my part.

brebs

Member

Registered: 2007-04-03

Posts: 3,742

Re: ALSA configuration files are not working

If I understand it correctly, -2 would correspond to a bitmask of only the 2nd bit. So you've got 2 soundcards jostling for just one position.

If I understand it correctly, -254 would be more sensible, to allow any position except the first.

Run "dmesg" to see if the error messages got captured.