Pontiac 2008 G6 - Manual (Page 186)

Radio(s)
Your vehicle has one of these radios as its audio
system.
If your vehicle has the Monsoon audio system, it has
eight speakers and an eight channel amplifier. The radio
displays MONSOON when the radio or the ignition is
turned on. See your dealer/retailer for details.
Radio with a Single CD Player
Radio with a Six-Disc CD Player
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