DTMF SBC SIP Verizon Fix - for me

[Jason Hendrix]

April 2019 - Our new Verizon SBC SIP DTMF was failing when getting to 3rd party auto attendants and made a  change to CUCM SIP Profile - attached - was the fix - when resetting the SIP truck it will drop all calls

PER TAC - As discussed make the change on the Sip profile of the trunk :

Early Offer support for voice and video calls to mandatory; what mandatory do refer :

A SIP Profile option, where Unified CM inserts a media termination point (MTP) if the media characteristics of the calling device cannot be determined (for example, for an inbound Delayed Offer call forwarded over an Early Offer SIP trunk).

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/srnd/collab10/collab10/trunks.html

[Maren Mahoney]

Is this an offer of helpful information that you have discovered, or do you have a question about it?

[Jason Hendrix]

This is what was discovered – TAC found the fix for us with this setting/option on our CUCM 11.5. This is not a question or request for an answer.