Certain Outbound Calls not Ringing

Here’s an odd one, maybe I’m missing something obvious.

I have a FreePBX distro running version 10.13.66-22 with all modules updated.

Calls to certain outbound numbers are not ringing on the callers side. It shows the call in progress to the user, and then sound immediately begins with the destination user either answering the phone or going to voicemail. I can reproduce on using certain phone numbers, but it will occur from any phone and any DID on our side.

Looking at the logs:

[2017-11-15 11:04:31] VERBOSE[11834][C-0000074f] app_dial.c: Called SIP/ATT_Outgoing_BE2/******3037
[2017-11-15 11:04:33] VERBOSE[11834][C-0000074f] app_dial.c: SIP/ATT_Outgoing_BE2-000006bc is making progress passing it to PJSIP/11-000008ec
[2017-11-15 11:04:34] VERBOSE[11834][C-0000074f] app_dial.c: SIP/ATT_Outgoing_BE2-000006bc is ringing
[2017-11-15 11:04:34] VERBOSE[11834][C-0000074f] app_dial.c: SIP/ATT_Outgoing_BE2-000006bc is making progress passing it to PJSIP/11-000008ec
[2017-11-15 11:04:55] VERBOSE[11834][C-0000074f] app_dial.c: SIP/ATT_Outgoing_BE2-000006bc answered PJSIP/11-000008ec

The call shows up just like any other call and gets a ringing response, but nothing is being generated. I have reports of this happening at many different numbers and am having employees log the calls where it happens. Let me know if any more information would help.

Thanks for any advice!