This guide explains how to connect a generic linux-compatible USB sound card to the CH3SNAS/DNS-323. In this example, a Conceptronic USB Sound adapter was used. It is a thumbdrive-size usb-stick based on the C-Media CM108 chipset, and features a stereo in- and output jack.
I am not an expert on this subject, so please feel free to correct this page if you feel the need to do so.
You will need to install the following kernel modules:
insmod kernel/sound/soundcore.ko; insmod kernel/sound/core/snd-page-alloc.ko; insmod kernel/sound/core/snd.ko; insmod kernel/sound/core/snd-hwdep.ko; insmod kernel/sound/core/snd-timer.ko; insmod kernel/sound/core/snd-pcm.ko; insmod kernel/sound/core/oss/snd-mixer-oss.ko; insmod kernel/sound/core/oss/snd-pcm-oss.ko; insmod kernel/drivers/usb/class/audio.ko; insmod kernel/sound/core/seq/snd-seq-device.ko; insmod kernel/sound/core/snd-rawmidi.ko; insmod kernel/sound/usb/snd-usb-lib.ko; insmod kernel/sound/usb/snd-usb-audio.ko;
Precompiled modules for firmware v1.03 can be found here: http://dev.skcserver.de/dns323/modules_v1.03/ (except for audio.ko).
Load the modules using insmod in the order listed above. You can cd into the modules-directory and copy/paste the lines above in your terminal. Plug in your sound card. Typing dmesg in the command line should show you something like this:
usbcore: registered new driver snd-usb-audio
and some entries for usbaudio.
Now you can chroot into debian. Create the devices in /dev like so:
cd /dev mknod -m 660 mixer c 14 0; chgrp audio mixer mknod -m 660 mixer1 c 14 16; chgrp audio mixer1 mknod -m 660 dsp c 14 3; chgrp audio dsp mknod -m 660 dsp1 c 14 19; chgrp audio dsp1
(taken from http://buffalo.nas-central.org/index.php/Add_a_USB_sound_card)
apt-get install sox and see if you can make some sound (substitute $1 for a sound file on the NAS):
sox -q $1 -t ossdsp /dev/dsp