irq problem with alsa modules

[grap]

Hello everyone,

I am trying to make my soundcard work, but it seems that I have an irq problem.

When I boot my system and do an lsmod, I have :

snd_intel8x0           33068  0 
snd_ac97_codec         59268  1 snd_intel8x0
snd_pcm_oss            48168  0 
snd_mixer_oss          16640  1 snd_pcm_oss
snd_pcm                85540  2 snd_intel8x0,snd_pcm_oss
snd_timer              23172  1 snd_pcm
gameport                4736  1 snd_intel8x0
snd_mpu401_uart         7296  1 snd_intel8x0
snd_rawmidi            23232  1 snd_mpu401_uart
snd_seq_device          7944  1 snd_rawmidi
snd                    50660  9 snd_intel8x0,snd_ac97_codec,snd_pcm_oss,snd_mixer_oss,snd_pcm,snd_timer,snd_mpu401_uart,snd_rawmidi,snd_seq_device
soundcore               9824  1 snd
snd_page_alloc         11144  2 snd_intel8x0,snd_pcm

lspci tells me :
0000:00:1f.5 Multimedia audio controller: Intel Corp. 82801DB (ICH4) AC'97 Audio Controller (rev 01)

But I have no sound.

So I've installed and compiled the alsa-source package for ubuntu, and have run :
$ ./utils/alsasound restart
Shutting down sound driver: /usr/sbin/alsactl: save_state:1061: No soundcards found...
done

that confirms me that there is a problem.

So I've unloaded the drivers with alsasound stop, and reloaded by hand :
$ modprobe snd-intel8x0
and have the following in /var/log/messages :

Mar 21 00:13:38 osborne kernel: ACPI: PCI interrupt 0000:00:1f.5[B] -> GSI 7 (level, low) -> IRQ 7
Mar 21 00:13:38 osborne kernel: unable to grab IRQ 7
Mar 21 00:13:38 osborne kernel: Intel ICH: probe of 0000:00:1f.5 failed with error -16

I might be worng but it seems that the irq that the driver wants to used is already used (by acpi if I uderstood well) so the driver is loaded but not working.
I'm not familiar with this type of problem. I've tried something like:
$ modprobe snd-intel8x0 irq=8
but had :
snd_intel8x0: Unknown parameter `irq'

Has anyone an idea about what I should try to have it working?

Thank you in advance.

--
Grap

PS: one precision that I forgot, aplay something.mp3 tells me No such device, it seems to try /dev/aloadCà and /dev/snd/controlC0.