AASTRA 51i User Guide

Model 51i IP Phone User Guide  83

3. The "Microphone Mute" field is enabled by default. The microphone is muted on 

the IP phone for Intercom calls made by the originating caller. To disable this 

field, uncheck the box.

4. The "Play Warning Tone" field is enabled by default. If “Auto-Answer” is 

enabled, the phone plays a warning tone when it receives in incoming intercom 
call. To disable this field, uncheck the box.

5. The "Allow Barge In" field is enabled by default. If “Allow Barge In” is enabled, 

the phone puts an active call on hold and answers the incoming Intercom call. To 
disable this field, uncheck the box.

6. Click 

 to save your settings.

Using Redial Key for “Last Number Redial”

The IP phone has an enhanced redial user interface that allows a user to quickly redial 
the last number that was dialed out from the phone. You can:

• Press the REDIAL button twice to redial the last number dialed.
• Press the REDIAL button once, scroll the list of numbers, then press the 

REDIAL button again to dial the number that displays on the screen.

The “last number redial” feature for the Redial key is static and is not configurable.

Note: If the Auto-Answer field is not checked (disabled), the phone rejects the 

incoming intercom call and sends a busy signal to the caller.