Bought new CM Sirus 5.1 headcans. When PC is idling i hear small scratching noises or when i move the mouse too. I installed Xonar DG tinking it was the onboard. Still the same issue. I have disabled Azailia Codec and moved the DG as far from the GPU as is possible. Ive tried front panel connections and the dual USB (a Sirus feature?!) and the only result is the USB is less interference. This issue is only prevalent during idle times -playing music and gaming i cant hear it. However it annoys the hell out of me!!