Mercedes-Benz 2009 S-Class Operator's Manual page 293

Problem
Should interference occur during the process
of storing a name, the Voice Control System
prompts you to repeat your voice entry a third
and fourth time. If the interference continues,
the dialog is stopped.
Voice Control System does not recognize
commands.
Possible cause/consequence
Both voice entries differ.
You have not operated the system from the
driver's seat.
You have spoken unclearly, too loudly or too
quietly.
A blower is set to the highest setting, vents
are pointed at microphones or wind noise is
being created through open windows.
Control systems
Voice Control troubleshooting
Suggested solution
X
Pronounce the voice entries both times in
the same manner.
X
Operate the Voice Control System only by
the driver as the microphone is geared to
the driver side.
X
Speak the commands in a continuous
manner using a normal tone.
X
Avoid loud disturbances.
Z
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