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press the TALK button. To hang up, press the TALK button again. To
reject a call, hold down the TALK button for 1 second.
Adjusting the Volume
Use the VOLUME UP and VOLUME DOWN
buttons to adjust the volume. Each
adjustment is followed by a tone.
When the minimum or maximum level has
been reached, a different beep can be heard.
Note: The INVISIO
B3 saves the last used volume setting when
To mute the headset microphone, press VOLUME UP + VOLUME
DOWN at the same time for three seconds. To un-mute, press both
buttons again for about 3 seconds. While muted, the headset beeps
twice every two seconds.
Note: Audio tones can be heard only when wearing the headset.
To answer a second call, press the TALK button for 1 second. The
headset places the active call on hold and answers the new call. To
switch back, press TALK again for 1 second.