Mute
Press the abutton to mute handset, headset or handsfree. The speaker light will flash slowly and the text “Mute” will appear on the screen. You will still be able to hear the caller, but they will not hear you. To toggle mute on or off, press a.
Note: If you place a muted call on hold, the phone automatically takes the call off mute when you reconnect to the call.
Making Calls from 480i CT Base Station
14/IP Phone User Guide