Set up 2-Way Intercom
2-way intercom is used to make a multi-party conference. The called parties will automatically answer the call into speakerphone mode and join the conference.
Note: Paging is typically one way for announcements only.
Go to PBX > Call Features > Paging and Intercom , click Add.
Set a 2-Way intercom group.
Paging Extension: Use the default or specify a number for the paging group.
Group Description: Enter a name for the paging group.
Device List: Choose the group members to the Selected box.
Duplex: if select the checkbox beside Duplex, it means 2-Way audio.
Click Save and Apply.
When you dial the intercom group number, the members in the group will automatically join the conference by speakerphone mode.