We had a similar situation connecting to a Mitel that would not produce ringback. We were able to fix it on the voice trunk connected to our soft switch. We had to be on firmware 5.3 to use the ringback command. Hope that helps. Could also be a ringback setting in your softswitch, sending an 180 or 183...
voice trunk T01 type sip
description "Connection to MetaSwitch"
caller-id-override number-inbound xxxxxxxxxx if-no-cpn
caller-id-override emergency-outbound xxxxxxxxxx
sip-server primary x.x.x.x
registrar primary 10.2.10.40
outbound-proxy primary x.x.x.x
ringback override 180
Thanks for posting! Generally speaking, there are two different ways the ring back would be handled for your scenario. The way it is handled is usually determined by the response from your PBX. If your PBX sends the Adtran unit a message that includes "inband audio available", that would indicate your PBX wants to play the audio. Since it does not support playing ringback, hopefully it is not sending that information. Alternatively, it could be sending the Adtran unit an Alerting message which would translated into a 180 Ringing message sent towards the carrier. In this case the carrier would provide ringback.
We would need to see the configuration from the unit and the output of the following debug commands fully understand the problem and make any recommendations.
debug sip stack message
debug voice verbose
debug isdn L2-formatted
If you can get access information to the unit or have your provider call us about the problem, we would be glad to help however we can. You can create an Adtran Technical Support ticket by calling 888-423-8726.
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