NVidia MPC 97 works, but anything is herd

[DevOne]

Hi,
currently i've a problem with alsa on macs using linux (gentoo kernel-2.6.31-r6)
Both have an nVidia MPC97 high definition and are configured in kernel as module (snd-hda-intel)
Sound card is successfully detected by linux and alsa; it seems to work, but i'm not able to hear any sound!
the strange is the interpretation of codec:

on iMac24 (iMac9,1):
cat /proc/asound/card0/codec#* |grep Codec shows: Codec: Realtek XXXX

on Macbook-pro (macbookpro5,3) the same command shows: Codec Generic XXXX ID XXXX
I notice that other guys have the same problem too.

Can you help me?

thanks
Gianni
_________________
Open-source Virtual Keyboard QT widget: http://www.qt-apps.org/content/show.php/VirtualKeyboard?content=107388
QT MosaicCrack RC: http://qt-apps.org/content/show.php/MosaicCrack?content=121832

[DevOne]

In kernel 2.6.33 there is a Cirrus Logic CD4206 codec, that is what windows now use.
Now i'm able to hear sound but only through headset!
_________________
Open-source Virtual Keyboard QT widget: http://www.qt-apps.org/content/show.php/VirtualKeyboard?content=107388
QT MosaicCrack RC: http://qt-apps.org/content/show.php/MosaicCrack?content=121832