See : http://alsa.opensrc.org/index.php/AlsaSharing

Make udev assign the right permissions to the sound devices, but putting the following in /etc/udev/rules.d/90-alsa-extra.rules :

# Fix up sound devices for all users  
NAME=="snd/*", MODE="0666"

In /etc/asound.conf, something along these lines :

pcm.card0 {  
type hw
card 0
# mmap_emulation true
}
pcm.dmixer {
type dmix
ipc_key 36739
ipc_key_add_uid false
ipc_perm 0666
slave {
# pcm "hw:0,0"
pcm "card0"
period_time 0
period_size 1024
buffer_size 8192
#periods 128
#rate 44100
rate 48000
}
bindings {
0 0
1 1
}
}

ctl.mixer0 {
type hw
card 0
}
pcm.dsnoop0 {
type dsnoop
ipc_key 36741
slave {
pcm "card0"
}
}
pcm.asym0 {
type asym
playback.pcm "dmixer"
capture.pcm "dsnoop0"
}
pcm.pasym0 {
type plug
slave.pcm "asym0"
}
# 'dsp0' is espected by OSS emulation etc.
pcm.dsp0 {
type plug
slave.pcm "asym0"
}
ctl.dsp0 {
type hw
card 0
}
pcm.!default {
type plug
slave.pcm "asym0"
}


Martin Andrews

{Finance, Software, AI} entrepreneur, living in Singapore with my family.