Hello, I'm using pjsua2 in conjunction with the classes and functions of pjlib for an application. But I'm having a little problem, which I could not solve. On the same specific network, I have two endpoints registered on a remote SIP server (public ip). When they are set to use STUN, I can do / accept INVITE, but the audio does not travel over the network. In the same environment, if one of the endpoints is not using STUN, audio travels normally. Another detail, with STUN enabled at both endpoints, if one of these endpoints is on another network, audio travels normally. However, in another network with the same characteristics (PJ_STUN_NAT_TYPE_PORT_RESTRICTED) according to the STUN resolution, the two endpoints "talk" normally. Evaluating the firewall of this first network, I found nothing that could be blocking this communication. Comparing the pjsip logs to the Xcode console, I could not find any information that could help me understand what's happening. If anyone can help me, Thank ​s​ . Thiago ​ Guimarães​ .