I am running Unity 5.x which has an Autoattendant configured. Sometimes when I dial the AA, the AA Opening greeting is played immediately, which is what it should be doing ideally. But there are times when the Unity AA opening greetingis heard after 3-4 rings and sometimes it take around 6 rings for the AA to play the opening greeting. I don't see a consistent behavior.
Similar behavior is seen when I press the messages button on the IP Phone.
Any suggestions to troubleshoot would be highly appreciated.