ECS N2U400-A sound not working

Hi –

I can no longer get the audio on my ECS N2U400-A motherboard to work except for the basic "beep," and I have the integrated AC97 audio set to "Auto" in the 1.0b BIOS. The board has an nForce2 chipset, but for audio the install CD and ECS website both use a C-Media 973x driver. I am running WinXP SP2.

I had been using the NVidia nForce2 audio driver and nvMixer app with no problems. (I am also using the nVidia unified driver 5.10 and latest forceware display driver 81.95.) I recently installed the latest nVidia audio version (4.62) and that seems to have messed things up. The audio no longer worked, and I got a "could not detect nVidia nForce hardware" error. I tried uninstalling it, rebooting, and reinstalling the older nVidia audio driver, but got the same problem. I then uninstalled nVidia audio, rebooted, and let Windows Update install the CMedia AC97 device (and Xear3D app), but the audio still didn't work and the app gave a "no mixer devices available" error. COntrol Panel>Audio and dxdiag can't find the sound HW either. (I also tried the older version of the driver that was on the ECS website, but had the same problem.)

With either audio driver, the appropriate device (C-Media AC97 audio device or nVidia audio codec) is listed as enabled without errors. I made sure that the devices were anabled for audio. mixing, and MIDI. I don't have any red-X's or yellow-!s.

With the Windows Update C-Media driver, according to the Xear3D app,the audio configuration is:
3D Audio Configuration: Xear3D CRL3D A3D1.0
Audio Codec: CMI9739A
Driver Version: 5.12.01.0049.1 (63)
Audio Controller: nVidia MCP2/MCPT Audio Controller
DirectX Version: DirectX 9.0c

Can anyone help me debug this problem?

-Thanks! LloydM