Polycom Conference Phone Owner's Manual page 27

Muting the Microphone
To mute the microphone:
During a call, press
The three console LEDs glow red to indicate that the other party
(or parties) cannot hear you. You can still hear all other parties
while Mute is enabled.
To turn off the Mute feature, press
To mute the microphone if you use external microphones:
Press on the phone or the
external microphones.
To turn off the Mute feature, press
Redialing Numbers
You can redial the last number you dialed, or search a list of
placed calls to find a previously-dialed number.
To redial the last number dialed:
Press .
To redial a previously dialed number:
1. Press , and then select Features > Call Lists >
Placed Calls.
2. The Placed Calls screen displays:
3. Scroll to the number you want to redial, and then press
the Dial soft key.
.
again.
button on the top of the
again.