I have a problem here with ringback tone on OXE.
/--PCM-> OPERATOR / ASTERISK <-SIP-> OXE <-- \ ˄ ˄ \--T2--> OPERATOR 2 | | | | ˅ ˅ SIP PHONE IP PHONE
Call from IP PHONE to OPERATOR 1 (PCM), RBT ok
Call from IP PHONE to OPERATOR 2 (T2), RBT ok
Call from SIP PHONE to OPERATOR 1 (PCM), RBT ok
Call from SIP PHONE to OPERATOR 2 (T2), RBT nok
So, only calls from SIP PHONE to OPERATOR 2 using T2 that you see this problem. I made a trace and the problem is that OXE doesn't send RTP packets until the called number answer the call, when you make a call you start hearing the destination speaker talking directly and the call remains mute until the answer.
Thanks for all.