See also:

Sound output
Switching on/off When the ignition is switched off: press ON/OFF button on the radio. Muting When the ignition is switched on or the engine is running: press the ON/OFF button on the radio. ...

Loss of the remote controls
Lost remote controls can be blocked by your service center. ...

Volume of spoken instructions
Turn the volume button while giving an instruction until the desired volume is set. The setting is stored for the remote control currently in use. ...