Program Sound 30 APS using the keyboard as follows:
1 Switch off Sound 30 APS in the FM mode and then immediately press the "Sound" and "4" keys at the same time until "Sound 30" appears in the display.
2 Press "UP" key until the "Speed-dependent volume control" menu and set using the rotary switch to the value "2".
3 Press "Up" key until the Light menu (background illumination) and set rotary switch to "ON".
4 Switch off Sound 30 APS so that the settings can be accepted.