Hi All, I have the 'on_create_media_transport()' callback implemented. However, it never gets called although I manage to get audio calls through. I gather that this must mean that default pjsip adapters get used instead of my custom ones. Is there any other reasons why this could be happening? Thanks, Mat --- avast! Antivirus: Outbound message clean. Virus Database (VPS): 171012-0, 12/10/2017 Tested on: 13/10/2017 10:54:48 avast! - copyright (c) 1988-2017 AVAST Software. https://www.avast.com/antivirus