Heres some suggestions I found at hardwareanalysis.com hope they help
There have to be caps on 2 jumpers of the "front panel audio connector"
(10-1 pin connector); look if there are caps on the "Lineout_R/Bline_OUT_R" and
Line out_L/BLINE-OUT_L" jumpers, if you dont use front panel speakers
OK . I am cured. Now hopefully I can help someone else.
As posted above.... THERE ARE JUMPERS FOR THE AUDIO CONNECTION. yes, my new board NEVER had the jumpers but they are a must for the sound problem.
See the post above for the details.... .......and also, if you don't install the 3com drivers correctly on a new WIN o/s install, your in for some crazy internet connection problems. Thanks to all that posted.....
I bought a new, rev. 2.0 A7N8X deluxe, everything was working perfect, except for no sound. I checked volume leves, outputs, cables, all ok.
The equalizer in winamp was moving, but no sound output.
I started reading this post, first thing i tried was removing the front audio panel jumpers. Still no sound. Then i put back the jumpers in the same position they were and wow! Sound was alive!
Just did that, no cardboard, didn't remove the mother from the case, only he jumperst. Hope that helps someone else. Very strange but it did work for me!