Making voice calls321. Press OPTIONS.2. Press MUTE.The IP Phone 1535 disables the microphone, and displays the Muteicon.To take a call off mute, press UNMUTE.Adjusting audio volumeTo adjust the volume level of an active call• Use the up and down arrow keys to increase or decrease volume.• Select Audio volume from the Options menu.Both of these methods change the volume of the IP Phone 1535 handset/handsfree speaker only, not the volume of the microphone.Use the following procedure to adjust volume from the Options menu:1. Press OPTIONS.2. Select Audio volume.3. Press OK.The screen displays current volume level (up to a maximum of five).4. Use the up and down arrows to adjust the volume to your desiredlevel.5. Press OK.Placing an active call on hold1. Press OPTIONS.2. Select Call hold.The IP Phone 1535 places the call on hold and displays the Call holdicon.With the call on hold, you can then receive an incoming call or initiate anew outgoing call. To switch between the new call and the on-hold call,press ALTERNATE (or select Alternate call from the Options list).
