I finally got my separate a/b/g card last night!! I called up Alienware to install it.
Once the card was seated, there was a black wire and a gray wire which would connect to either the main connection or auxilliary connection.
The tech support guy HIGHLY recommended that the gray wire stay disconnected and covered up. So that left the black wire to connect to the main connector. This gray wire was probably the source of sound interference.
I snapped some pics during the operation and I'm willing to post them up if someone can host them...