We have setup a freeswitch / fusionPBX server and are using sipjs as webrtc clients. What we cant figure out is how to make presence work. We subscribe on the server, get an ok back, but we never get a notify with status info about the peers.
NetworkLab is experts in VoIP and freeswitch particularly. We can help you figure out freeswitch presence issue. Our reach experience will help complete the project quickly and on time