I have a Kamailio box which I use as a uac_client. We register a bunch of accounts to remote providers. The box relays incoming calls to a FreeSwitch box. We encountered a strange problem on one account.

Kamailio relays the call to my FreeSwitch box successfully but routes the ACK itself which is the reply of 200Ok. I believe this is a provider related issue but I need a technical explanation. Does anyone have any idea?

Here is the packet capture: https://pastebin.com/PA8StiWY

Thanks,

--