Dear all, My partner company are using an AudioCodes PBX system. But now they are expanding their branch, they want to set up FreeSWITCH PBX in new branch. The requirement is the new FS PBX server can communicate all extension of the current AudioCodes PBX system via internal SIP trunk. I have set up the sip trunk, the result is that two system can call together. But If I make call from FS's extension to AudioCodes's extension, the call is connected and we can talk together, but it will be auto disconect after 10 seconds from AudioCodes side. The phone status at FS side is still connected Otherwise If I make call from AudioCodes's extension to FS's extension, It run well, no time limit. I have checked the console log, it show that the call is still connected at FreeSWICH side, only AudioCodes side is disconnected. If any one understand the problem please help me. Thanks you very much! Em Nguyen