It's really strange that it works fine on my A8N-SLI and not on SE, Premium or Deluxe models. What's the damned difference????????
Here's a tutorial I found on a spanish forum, sorry for the typos, I'm latino:
Step 1: Going down :P
>>Start Windows
>>Go to Control Panel and open your Device Admin
>>Search for the Sound device (AC'97 something) and double click it.
>>Go to Details and write down these numbers:
VEN_XXXX mine is 10DE
DEV_XXXX mine is 0059
>>Reboot and get the hell out of there
Step 2: Back to heaven
>>Start Zephyroth's Leopard
>>Open a terminal
>>Login as admin (sudo su)
>>Go to this folder:
/System/Library/Extensions/AppleAC97Audio.kext/Contents/PlugIns/AppleAC97AudioIntelICH.kext/Contents
>>nano Info.plist
>>Find this line: <key>NVIDIA AC97 Audio</key>
>>Below you'll see something like this: <string> 0x026b10de 0x005910de blahblablah </string>
>>Add your vendor and ID here this way:
0x(here your dev ID)(and here your vendor) in my case it's 0x005910de
>>Save with Ctrl+o and exit with Ctrl+x
>>chown -R root:wheel /System/Library/Extensions
>>chmod -R 755 /System/Library/Extensions
>>Reboot and check for audio output