Good luck. I've tried Audience, Monster, AR, cheapies, Belden homemade, and just about anything else I can put my hands on and I still get hum.
How loud is your hum? Do you get 2 kinds of hum or just 1? I get an idle hum and a volume dependent one. I've also tried different power cables, a cheater plug (3-2 prong adaptor) and moving the preamp far away from the rest of the system.... all with no luck. I've even tried mu-metal barriers...
It does sound really good otherwise. Gary's at CES and I'm waiting to talk to him about the hum.