CITROEN DS5 Owner's Handbook Manual page 270

04 NAVIGATION - GUIDANCE
ADJUSTING THE GUIDANCE SPEECH SYNTHESIS
ADJUSTING THE VOLUME/DEACTIVATION
The volume of messages can be adjusted during the transmission
of the message using the volume adjustment control.
Press NAV to display the " Navigation -
guidance" menu.
Select " Guidance options " and confi rm.
Select " Set speech synthesis" and
confi rm.
The volume setting of guidance messages is also accessible via the
"SETUP" / " Voice synthesis " menu.
Select the volume graph and confi rm.
Adjust the volume to the desired level
and confi rm.
Select "Deactivate " to deactivate voice messages.
Select " OK " and press the dial to
confi rm.