2008 GMC Acadia Owner's Manual - Page 269

Rear Audio Controller (RAC) SRCE (Source): Press this button to switch between the radio (AM, FM), XM™ (if equipped), CD, and if your vehicle has these features, DVD, front auxiliary, and rear auxiliary. > (Mute): Press this button to silence the system. Press this button again, or any other radio button, to turn the sound on. Your vehicle may have the Rear Audio Controller (RAC). With RAC you can control certain radio functions. Press the down or up arrows to go to the next or to the previous radio station stored as a favorite. When a CD/DVD is playing, press the down or up arrows to go to the next or previous track or chapter. + / − x (Volume): Press the plus or minus volume buttons to increase or to decrease the volume. xw (Next/Previous): Theft-Deterrent Feature THEFTLOCK® is designed to discourage theft of your vehicle's radio. The feature works automatically by learning a portion of the Vehicle Identification Number (VIN). If the radio is moved to a different vehicle, it does not operate and LOC, LOCK, or LOCKED could display. With THEFTLOCK® activated, the radio does not operate if stolen. ©SEEK ¨: Press the SEEK arrows to go to the previous or to the next radio station while in AM, FM, or XM™ (if equipped). Press the SEEK arrows to go to the previous or to the next track or chapter while sourced to a CD or DVD slot. 3-127