Hi there & Happy New Year to you all.

Here we have MB: Tyan Tomcat n3400B, no on-board sound, CPU: AMD Opteron, OS: Window xp/ Linux fc7 kernel 2.6.25 x86_64 dual boot. Generally everything works fine for quite some time except sound. I have a PCI 32bits C-Media Electronics Inc CM8738 sound card installed and it goes fine with windows. In Linux it works with alsa ONLY IF:
Linux was booted AFTER windows && sound settings were changed in windows
otherwise it doesn't.
Sometimes 'udev' hangs up during a boot while executing 'alsa-rules'. Personally I don't use sound on this box at all and even don't notice if it is there. It comes to annoyance when someone suddenly wants to play music or watch DVD movie on it while the sound was missing.

So when the sound is on I have lspci -v:

01:07.0 Multimedia audio controller: C-Media Electronics Inc CM8738 (rev 10)
Subsystem: C-Media Electronics Inc CMI8738/C3DX PCI Audio Device
Flags: bus master, medium devsel, latency 64, IRQ 19
I/O ports at e800 [size=256]
Capabilities: [c0] Power Management version 2

and when it is off:

01:07.0 Multimedia audio controller: C-Media Electronics Inc CM8738 (rev ff) (prog-if ff)
!!! Unknown header type 7f

Sound driver stays loaded at all the time:

snd_cmipci 45216 0
gameport 20112 1 snd_cmipci
snd_seq_dummy 8644 0
snd_seq_oss 36800 0
snd_seq_midi_event 12608 1 snd_seq_oss
snd_seq 59104 5 snd_seq_dummy,snd_seq_oss,snd_seq_midi_event
snd_pcm_oss 46976 0
snd_mixer_oss 21568 1 snd_pcm_oss
snd_pcm 87368 2 snd_cmipci,snd_pcm_oss
snd_page_alloc 15440 1 snd_pcm
snd_opl3_lib 16960 1 snd_cmipci
snd_timer 29072 3 snd_seq,snd_pcm,snd_opl3_lib
snd_hwdep 15112 1 snd_opl3_lib
snd_mpu401_uart 13568 1 snd_cmipci
snd_rawmidi 31168 1 snd_mpu401_uart
snd_seq_device 13140 5 snd_seq_dummy,snd_seq_oss,snd_seq,snd_opl3_lib,snd _rawmidi
snd 68680 12 snd_cmipci,snd_seq_oss,snd_seq,snd_pcm_oss,snd_mix er_oss,snd_pcm,snd_opl3_lib,snd_timer,snd_hwdep,sn d_mpu401_uart,snd_rawmidi,snd_seq_device
soundcore 13216 1 snd

I have found quite a lot of complains about this card on different forums but it doesn't seem to be a problem this time as it works fine with windows and 'after' windows. Does it sound like IRQ conflict?

Any help would be greatly appreciated.
Many thanks