On Sunday 10 February 2008 06:58, Tim wrote: > On Sat, 2008-02-09 at 18:18 -0500, Tom Horsley wrote: > > Why any sane kernel startup sequence would initialize any > > removable devices before any fixed devices is a separate > > question :-). > > I can imagine one reason: The thought that an "added on" device might > be to replace a built-in device that you can't remove. > > However, if I'm asked to configure what is my default sound card (as > during the first-boot sequence), I expect that default to stay no matter > what else is added. Hi Tim. The way I've always understood this, regarding USB devices that use snd-usb-audio, is that because the USB comes up early in the boot process, anything that resembles an audio device (like my usb midi keyboard), gets set as card0. If your actual soundcard is aliased as card0, with the options line showing "index=0", it is unlikely to show up in /proc/asound/cards, as snd-usb-audio has already grabbed card0. Saying that though, you will probably still see that the modules have been loaded for your actual soundcard in /sbin/lsmod | grep snd, but because the soundcard isn't in /proc/asound/cards, it won't work. The fix I've had to use since FC1, and on other distro's too, is to set alias, and options lines in /etc/modprobe.conf for snd-usb-audio, as below. alias eth0 8139too alias scsi_hostadapter libata alias scsi_hostadapter1 pata_via alias snd-card-0 snd-emu10k1 options snd-card-0 index=0 options snd-emu10k1 index=0 alias snd-card-1 snd-usb-audio options snd-usb-audio index=1 options snd-bt87x index=2 options bttv automute=0 options tuner port2=0 pal=I install pcspkr /bin/true The module snd-bt87x above, is another notorious one, along with some modem modules, that like to grab card0, before anything else can. It's the sound capture module for my TV card, and some distro's have default options lines for these problematic modules, and set them as "index=2", thus stopping them grabbing card0. If you have more than one audio device on the USB, it get's a little more complex, and you have to specify them by their PID's (product id's), and VID's (vendor id's). So for example you could have your webcam, and usb midi keyboard always taking the same position. I'll have to look for the exact details on this, as they were on the alsa-user list. Just some Sunday afternoon (Northern France) passing the time stuff. Nigel.
