nforce sound problems

[Sasha Tsykin]

Hey,

I have a Gigabyte K8NS Ultra-939 motherboard, and am trying to use the 
onboard sound. It has a standard nvidia inbuilt soundcard (Realtek 
ALC880). I googled for a solution to nvidia solution for surroung sound. 
When I type nvmixer, and I try to change settings, it tells me 
"[operation] failed", for volume change, or any of the swaps. I have the 
Nvidia nforce

Hoping somebody knows how to fix this,

Sasha