I've been trying to get rid of annoying sound in my headphones for some time now, without any success. The noise is a pulsating hum... think its about 50Hz according to some sound analyzing software.
I was originally using Roccat Kave headphones through the built in audio on my P5N-T Deluxe mobo. This sound appeared immediately. The support at Roccat said it may be a driver problem and thought a new sound card may solve the problem (interference in mobo or something).
Installed a Creative PCI Express X-Fi Titanium card... sound still there!
The only solution i've found is holding the cable... not easy to do when you require two hands! But this solution, and the 50Hz signal, may imply the problem is related to grounding or some other type of interference.
Any help would be appreciated as no one i've spoken to can help.