See also:

Volume control switch
Press the switch to the “+” side to increase the volume. Press the switch to the “−” side to reduce the volume. A number indicating the volume will be shown on the audio display. ...

Fuse panel located in the passenger compartment
...

Bluetooth® audio (type C and D audio)
This function enables you to play back audio sources from Bluetooth® audio devices. You need to register the Bluetooth ® audio device in the system before using it. ...