i had an internal creative soundcard some 5 years back. sound was pretty perfect with dt990 pro and sz2000. my current creative usb soundcard has more noise :(
You'd have to put it all the way around it, including near the connector. Obviously you can't put it inside the connector, but that's another avenue for noise to get in. Outisde the box of noise with it's own box of insulation is a much calmer place.