All attendees and leaders on a conference call can adjust their call preferences whilst on the call simply by inputting the following commands on your keypad:
Mute & unmute yourself
Pressing *1 toggles mute on and off.
How to increase the conference call volume
Pressing *4 decreases the volume and pressing *6 increases the volume of your call.
How to increase your volume to other participants
Pressing *7 decreases your volume and pressing *9 increases your volume to other participants.
These commands can be input at any time during the conference call.