Hello, At r15025 the ringback tone handling has changed. The old method: When ringback was set, early media was ignored, meaning that if you got 183 with SDP, ringback was generated locally. The new way: When ringback is set, the ringback tone is generated only when there is no early media (thus 180 w/o SDP or 183 w/o SDP). When early media is presented, it will be used as ringing indication. To get the same behaviour as before r15025, you have to set the following: ignore_early_media=true ringback Some wiki pages were changed to report the new behavior. Many thanks for guys for fix/feature, especially for anthm and bkw. Kind regards, Tamas ps.: issue was related with FSCORE-454.