No sound on Medion P4 system with AC97

[NevadaDave]

Hello All,

I finally read the sticky about how to ask a question, so I'll try this again with a better topic and description, and eliminate some deadwood from the post.

I am running 10.4.6 (JaS load) on a Medion PC with a Microstar MS-6533-L motherboard, with a 2.4 GHz P4, with SSE2. The chipset is a SiS 645DX. OS is loaded onto a separate 40 GB HD, and I change the BIOS to tell it to boot form this HD, rather than the 120G XP HD.

I have been unable to get sound working.

I have the Realtek AC97 onboard sound. The vendor/device ID comes up as 0x70121039.

If I apply the kext mod (adding the vendor/device string into the IntelICH kext) as shown in a variety of places, I will get a volume indicator on the menu bar after rebooting, and if I go into preferences, I will see the AC97 audio as an output device. However, if I actually try to USE the sound, whether trying the speaker setup test (which gives me a one-time burst of white noise) or running iTunes, the system locks up pretty hard - will not respond to mouse clicks (although the mouse pointer can be moved) or keyboard. The only thing I can do is a push the power button & reboot, then edit out the string I added. I have tried adding the dev/vendor string to the ICH6, the ICH5, the ICH4 and the nVidia sections of the kext with the same result. I realize that this seems to be a common issue, and that everyone is busy with their own problems - but does anyone have anything else I can try? Is there any theory as to why some folks seem to be able to get their AC97 sound to work, and many others don't?

I apologize for multiple posting this problem - I didn't see any way to delete the previous posts.

Thanks much!