Adjusting the sensitivity of the radio volume control.
1. Get in the car, door closed, key to position 1 (accessory).
2. Turn the radio off, then back on.
3. Without touching any other buttons, press and hold the 'm' key for 10 seconds or so (use the RDS button
on cars with the Navigation system) until the display changes.
4. Use the '+' and '-' buttons to change the display to 'GAL'.
5. Use the radio preset buttons (1 - 6) to set the sensitivity (1 = least, 6 = most).
6. Turn the radio back off and on to save the setting.