Thanks for posting! I believe I found an associated Technical Support ticket for this problem. It appears that this issue will be resolved in R11.3.0 firmware. If I am mistaken about matching this up to a support ticket, please let me know.
Thanks for the reply, is it possible to get the new firmware in advance so we can test it out. Our customer is experiencing this issue as we speak and would like to try it out as soon as posible. Yes, i believe we are the one who created that case. Just posted the same issue here in this forum hoping for somebody having the same issue.
I am wondering if someone could help me with the configuration of SIP to BRI, I cannot find a BRI configuration guide on the adtran community site, or published docs.