[JasonAFC]

I picked up the Asus DGX a couple of weeks ago and this has been an issue from day one.
 
When I change the Analog Out to 'Headphone' this low hissing sound starts immediately but the same problem does not occur if they're set to '2 speakers'. http://i.imgur.com/93m0gSn.png?1
 
I can sit there and switch between the two settings and the hissing starts and stops. So this got me thinking it has something to do with the headphone amplifier...
 
It gets less noticeable and drowned out at higher volumes but obviously that's not ideal. I've tried different headphones, reinstalling the card and the unified drivers.
 
Any ideas what could be the problem and how I might solve it?
 
Thanks for reading.

 

[PurpleAngel]

Did you disable the motherboard's on-board audio? in the BIOS.

 

[JasonAFC]

Thanks for the reply.
 
Yes, I did that before installing the card and have since tried to re-enable it but it makes no difference.