Mercedes-Benz S-Class Cabriolet 2017 Owner's Manual page 254

Switching the sound on/off
On the multifunction steering wheel
On the multimedia system
To mute: press volume control 1.
#
The 8 symbol appears in the status line
of the display.
You will also hear traffic announcements and
navigation announcements even when the
sound is muted.
Multimedia system 251
To switch on: change the media source or
#
turn volume control 1.
Adjusting the volume
On the multifunction steering wheel