2003 GMC Safari Owner's Manual - Page 171

Rear Seat Audio (RSA) PWR (Power): Press this button to turn the rear seat audio system on or off. The rear speakers will be muted when the power is turned on. You may operate the rear seat audio functions even when the primary radio power is off. VOL (Volume): Press this knob lightly so it extends. Turn the knob to increase or to decrease volume. Push the knob back into its stored position when you're not using it. The upper knob controls the upper headphone and the lower knob controls the lower headphone. This feature allows rear seat passengers to listen to any of the music sources: radio, and CDs. However, the rear seat passengers canonly control the music sources that the front seat passengers are not listening to. For example, rear seat passengers may listen to a CD through headphones while the driver listens to the radio through the front speakers. The rear seat passengers have control of the volume for each of headphones. set Be aware that the front seat audio controls always override the rear seat audio controls. AM FM: Press this button to switch between AM, FM1 and FM2. If the front passengers are already listening to the radio, the RSA controller will not switch between the bands and cannot change the frequency. Press AM FM to return to listening to the radio when a CD is playing. The inactive tape or CD will remain safely inside the radio for future listening. A SEEK : While listening to AM, FMI or FM2, press the up or the down arrow to tune to the next or to the previous station and stay there. This button is inactive if the front radio is in use. v 3-46