See also:

Adjusting the volume
Turn the knob until the desired volume is selected. The setting is stored for the remote control currently in use. The vehicle automatically adjusts the volume of the microphone on the telephone ...

Have maintenance carried out
Have vehicles maintained regularly to achieve optimal vehicle economy and operating life. Have the maintenance carried out by your service center. Please also note the BMW Maintenance System ...

Switching off automatically
System switches off: above approx. 9 mph/ 15 km/h. Switch on the system again if necessary. ...