Aastra 9143i Series Administrator's Manual page 692

IP Phone Administrator Guide
Advanced Operational Features
Aastra Web UI
Step Action
1 Click on Advanced Settings->Global SIP->RTP Settings.
2 Enable the "Two Call Support" field by checking the check box.
(Disable this field by unchecking the box).
3 Click
Note: The session prompts you to restart the IP phone to apply the configuration settings.
4 Select Operation->Reset and click
6-12
to save your settings.
.
41-001160-03 Rev 00, Release 2.5