No.... Simply get a PIE adapter from
www.crutchfield.com... This will give you 2 rca inputs (left and right) You can jack in any item you want, external sat PNP unit, ipod, walkman, et-al via a 1/8th stereo mini>>dual male rca adapter (4 bux at radio shack) Once the PIE adapter is pluged in, the AUX will use the input from those lines.
Here's the link
http://www.crutchfield.com/S-jz1sXuM...rch=GM+and+AUX