Switching the microphone to mute
When a call is active, the microphone can be muted.
1. "Telephone".
2. "Active calls".
3. 
"Microphone mute"
A microphone that has been switched to mute is automatically reactivated:
▷ When a new connection is established.
▷ When switching between call parties.
See also:
At a glance
These overviews of buttons, switches and
displays are intended to familiarize you with your
vehicle. You will also become quickly acquainted
with the available control concepts and options. ...
Operation
Adjusting the volume
Turn the knob until the desired volume is reached. The setting is stored for
the remote control currently in use.
The vehicle automatically adjusts the volume of the microphon ...
Switching on/off
Press the button. ...