I've been working on this all weekend and I can't figure it out. Here's the setup and problem - I have a Creative Z2 Platinum sound card, a Viewsonic N6 video processor, and set of Klipsch 2.1 Pro ...

There is a low pitch hum in my computer speakers when I have the cable connection plugged in or when either the shield or the core is touching the card. Does anyone know what is going on here?