Yes, go ahead and open a TAC case. To speed up the process, you can open a TAC from this discussion, so TAC team will start your case first checking all the troubleshooting steps we have done until now, so you can save time and avoid re-test.
Please rate replies and mark question as "answered" if applicable.
I have the same problem with CUCM 9.1 and TC 6.2. What was the resolution for the TAC case you raised?
Go to >> CUCM Administration >> System >> Enterprise Parameters Configuration >> Set your >> "Organization Top Level Domain". I believe that alone with fix the issue. If not, set as well, "Cluster Fully Qualified Domain Name". Please post if this works for you.
Thanks for your reply. I already had the customer's domain set in the Enterprise Params top domain and cluster domain name. The fix was setting the endpoints to use the 'Standard SIP Profile For TelePresence Conferencing' which has the checkbox ticked for '