Switching the microphone to mute
When a call is active, the microphone can be muted.
1. "Telephone"
2. "Active calls"
3. 
"Microphone
mute"
A microphone that has been switched to mute is automatically reactivated:
▷ When a new connection is established.
▷ When switching between call parties.
See also:
Opening the Options menu
Press the button.
The "Options" menu is displayed.
Additional options: move the controller to the
right repeatedly until the "Options" menu is displayed.
Options menu ...
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Deleting the button assignments
1. Press buttons 1 and 8 simultaneously for
approx. five seconds.
2. "OK" ...