I have an Asterisk server connected to a Nortel Pbx via an E1. Everything works fine, I get calls in and out with callerid. The problem that has been reported to me is the following scenario:
A call comes in from the PSTN and is answered by Asterisk. The person dials the operator (1000) which is on the Nortel side so connection is made through the E1. The operator answers and then transfers the call back to a SIP extension on the Asterisk (1303). The result is no audio and a dropped call.
My main theory at the moment is that when the receptionist hangs up after the transfer the E1 drops on the Nortel side. Anyone here with this type of integration seen this problem?