[Solved] Alsa Sound Card Numbering Not Persistant Between Boots

Question

Hello,
I'm having trouble with alsa and my multiple sound cards. Sometimes when I boot, I get the following output from "aplay -l"
**** List of PLAYBACK Hardware Devices ****
card 0: SB [HDA ATI SB], device 0: ALC889A Analog [ALC889A Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: SB [HDA ATI SB], device 1: ALC889A Digital [ALC889A Digital]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 2: Generic [HD-Audio Generic], device 3: HDMI 0 [HDMI 0]
Subdevices: 1/1
Subdevice #0: subdevice #0
However, I also see this after other boots:
**** List of PLAYBACK Hardware Devices ****
card 1: SB [HDA ATI SB], device 0: ALC889A Analog [ALC889A Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 1: SB [HDA ATI SB], device 1: ALC889A Digital [ALC889A Digital]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 2: Generic [HD-Audio Generic], device 3: HDMI 0 [HDMI 0]
Subdevices: 1/1
Subdevice #0: subdevice #0
Because the card numbering is not consistant, I'm having a great deal of trouble (if the card is 0, then I don't need an asoundrc, but if it's 1, I do). It also breaks my volume panel applet for the alsa card number to often change (volumeicon - from the AUR). Is there a way to force a certain device to always be card number 0?
Thanks for any help.
-Sean
Last edited by szim90 (2012-01-15 02:01:54)

Answer 1

Thank you for your response, karol.
I ran 'udevadm info -a -p /sys/class/sound/card1/' as was able to get the following information:
looking at device '/devices/pci0000:00/0000:00:14.2/sound/card1':
KERNEL=="card1"
SUBSYSTEM=="sound"
DRIVER==""
ATTR{id}=="SB"
ATTR{number}=="1"
looking at parent device '/devices/pci0000:00/0000:00:14.2':
KERNELS=="0000:00:14.2"
SUBSYSTEMS=="pci"
DRIVERS=="snd_hda_intel"
ATTRS{vendor}=="0x1002"
ATTRS{device}=="0x4383"
ATTRS{subsystem_vendor}=="0x1458"
ATTRS{subsystem_device}=="0xa102"
ATTRS{class}=="0x040300"
ATTRS{irq}=="16"
ATTRS{local_cpus}=="00000000,0000000f"
ATTRS{local_cpulist}=="0-3"
ATTRS{numa_node}=="0"
ATTRS{dma_mask_bits}=="64"
ATTRS{consistent_dma_mask_bits}=="64"
ATTRS{broken_parity_status}=="0"
ATTRS{msi_bus}==""
looking at parent device '/devices/pci0000:00':
KERNELS=="pci0000:00"
SUBSYSTEMS==""
DRIVERS==""
I'm completely new to writing udev rules; would the proper procedure be to write something like this:
DEVPATH=="/devices/pci0000:00/0000:00:14.2/sound/card*" ATTRS{number}="0"
or will that happen too late in the boot process (after the card has already been assigned a number)?
Perhaps it would be easier to work through alsa itself? I know I can get sound consistantly by calling out the card in asoundrc:
pcm.!default { type hw card SB }
ctl.!default { type hw card SB }
But this seems to disable dmix (software mixing). Is there a way to re-enable dmix from the asoundrc (and would that be easier than trying to work in udev)?
Regards,
Sean