Speed Dependent Volume (If equipped)
WARNING: This page is about a different car, the 2008 Pontiac G8. However, it is still accessible from the selected car via links, so may be relevant.
With Speed Dependent Volume (SDV), the audio system will adjust automatically to make up for road and wind noise as you drive, by increasing the volume as vehicle speed increases. The SDV adjustment range for the radio with a single CD player is between OFF and CUR 6, and the adjustment range for the radio with a six-disc CD player is between 0 and 5.