Hello and thank you for posting to our forum.
In order to give you a complete answer, I would need to see the ISDN Q.931 debug from the ADTRAN. If you can access the CLI, enter the command:
debug isdn l2-formatted
This turns on the Q.931 messaging so we can see the sent and received PRI messages. In one of the messages, there is an Information Element (IE) the ADTRAN thinks should be present. A combination of this debug and that console message should be enough to figure this out. Make sure you do the following prior to turning on the debug:
- enlarge your session window so the debug output is not truncated
- increase the session buffer or log the session output to a .txt file
Now all you need to do is make calls to reproduce the issue or let it happen on its own. When you get the debug with the console message, post it on here so we can look at it. You may want to scrub the Calling/Called Party Numbers out for privacy.
Verify that the ISDN switch type on the TA900 matches that of the PBX. Most common today is National NI-2 but DMS-100, AT&T-4ESS and Lucent-5ESS are other options. If you have a choice, National NI-2 is the most flexible in terms of caller-name display and other enhancements.
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