SDP is arriving delayed

Hi. I’m having some troubles after I upgraded from asterisk 1.8 to 11.17 version. What’s happening is that between the 180 Ringing, and the 200 OK (SDP) messages, exists a delay of almost 15-16 seconds, causing the audio to start being listened in the calling party, a couple seconds after it started to be played in the called party. This problem occurs only when I’m calling a cellphone, and the call is sent to mailbox. Here’s the call flow where you can see what I’m talking about.

Any other info will be provided as needed.

Dialplan and verbose level 5 or higher logs.

Yeah, complete Asterisk console output is needed for this. There’s nothing abnormal in what you’ve shown. It might be that the upstream isn’t answering as immediately as you’d expect in that case.