I just bought a very nice pair of headphones from Newegg, and the sound quality is a lot better than my previous cheap headphones. Unfortunately, the headers for my front-panel audio ports are located right under the edge of my video card, and with the better headphones I can hear a faint-but-constant digital chattering (like a dial-up modem), which gets quite loud if I put the video card under load.

Any ideas on how to reduce the cross-talk from the GPU?