Hello all I have a mixer/player application that uses a firewire audio I/O board. It is used for meetings with few microphones and played media. I have the need send the audio stream to a SIP server. I built in objective-C a simple app that enable me to test the connection with the SIP server site using pjsua calls and I can send and transmit the audio from my mac. Now I need to connect the sound output of the mixing AudioUnit to the input of the conference call and optionally the media coming from the sip trunk to an AudioUnit input. The pjsua will have no audio devices. What would be the best way to achieve this? Thanks Roberto