AT&T 7406BIS - Manual (Page 55)

To prevent other party 1 Press [ Mute ]
from hearing you
●
Red light goes on and party cannot hear you
Note: The Mute
feature can also turn
2 Press [ Mute ] again to resume talking to party
off the microphone ●
Red light goes off and other party can hear you again
associated with the
handset.
To change from
speakerphone to
handset
1 Lift handset and talk
● Green light next to [ Speaker ] goes off
To change from 1 Press [ Speaker ]
handset to
●
Green lights go on next to [ Speaker ]
speakerphone
2 Hang up handset