Very good catch!! At least 50% working, but no sound (sound device is completely ignored). Question. How can i manually set the sound device here? Normally pjsua_call_make_call() does it on its own. // If URL is specified, make call to the URL. if (argc > 1) { // TIPS: Peter Lukac @pjsip status = pjsua_set_null_snd_dev(); if (status != PJ_SUCCESS) { textcolor(BRIGHT, RED, BLACK); error_exit("Error even for NULL!!!", status); } pj_str_t uri = pj_str(argv[1]); status = pjsua_call_make_call(acc_id, &uri, 0, NULL, NULL, NULL); if (status != PJ_SUCCESS) { textcolor(BRIGHT, RED, BLACK); error_exit("Error making call", status); } } Note: I also tried to build the pjsua_app.c but it's not getting compiled. Thanks Regards N.B: While using NULL, this is what PJ shows, which is good working signal, but there is no SOUND. [root at example mysip]# ./myapp sip:5000 at 78.23.84.212 16:14:15.516 os_core_unix.c pjlib 1.6-trunk for POSIX initialized 16:14:15.519 sip_endpoint.c Creating endpoint instance... 16:14:15.519 pjlib select() I/O Queue created (0x86a81c0) 16:14:15.519 sip_endpoint.c Module "mod-msg-print" registered 16:14:15.519 sip_transport. Transport manager created. works 16:14:15.520 sip_endpoint.c Module "mod-pjsua-log" registered 16:14:15.520 sip_endpoint.c Module "mod-tsx-layer" registered 16:14:15.520 sip_endpoint.c Module "mod-stateful-util" registered 16:14:15.520 sip_endpoint.c Module "mod-ua" registered 16:14:15.520 sip_endpoint.c Module "mod-100rel" registered 16:14:15.520 sip_endpoint.c Module "mod-pjsua" registered 16:14:15.520 sip_endpoint.c Module "mod-invite" registered 16:14:15.522 pa_dev.c PortAudio sound library initialized, status=0 16:14:15.522 pa_dev.c PortAudio host api count=1 16:14:15.522 pa_dev.c Sound device count=0 16:14:15.523 pjlib select() I/O Queue created (0x86aed9c) 16:14:15.523 conference.c Creating conference bridge with 254 ports 16:14:15.546 sip_endpoint.c Module "mod-evsub" registered 16:14:15.546 sip_endpoint.c Module "mod-presence" registered 16:14:15.546 evsub.c Event pkg "presence" registered by mod-presence 16:14:15.546 sip_endpoint.c Module "mod-mwi" registered 16:14:15.546 evsub.c Event pkg "message-summary" registered by mod-mwi 16:14:15.546 sip_endpoint.c Module "mod-refer" registered 16:14:15.546 evsub.c Event pkg "refer" registered by mod-refer 16:14:15.546 sip_endpoint.c Module "mod-pjsua-pres" registered 16:14:15.546 sip_endpoint.c Module "mod-pjsua-im" registered 16:14:15.546 sip_endpoint.c Module "mod-pjsua-options" registered 16:14:15.546 pjsua_core.c 1 SIP worker threads created 16:14:15.546 pjsua_core.c pjsua version 1.6-trunk for i686-pc-linux-gnu initialized 16:14:15.547 pjsua_core.c SIP UDP socket reachable at 78.23.84.212:5067 16:14:15.547 udp0x86bd580 SIP UDP transport started, published address is 78.23.84.212:5067 16:14:15.547 pjsua_media.c RTP socket reachable at 78.23.84.212:4000 16:14:15.547 pjsua_media.c RTCP socket reachable at 78.23.84.212:4001 16:14:15.548 pjsua_media.c RTP socket reachable at 78.23.84.212:4002 16:14:15.548 pjsua_media.c RTCP socket reachable at 78.23.84.212:4003 16:14:15.548 pjsua_media.c RTP socket reachable at 78.23.84.212:4004 16:14:15.548 pjsua_media.c RTCP socket reachable at 78.23.84.212:4005 16:14:15.549 pjsua_media.c RTP socket reachable at 78.23.84.212:4006 16:14:15.549 pjsua_media.c RTCP socket reachable at 78.23.84.212:4007 16:14:15.549 sip_endpoint.c Module "mod-unsolicited-mwi" registered 16:14:15.549 pjsua_acc.c Account sip:2000 at 78.23.84.212 added with id 0 16:14:15.549 endpoint Request msg REGISTER/cseq=27258 (tdta0x86c95f8) created. 16:14:15.549 tsx0x86ca664 Transaction created for Request msg REGISTER/cseq=27259 (tdta0x86c95f8) 16:14:15.549 tsx0x86ca664 Sending Request msg REGISTER/cseq=27259 (tdta0x86c95f8) in state Null 16:14:15.549 sip_resolve.c Target '78.23.84.212:0' type=Unspecified resolved to '78.23.84.212:5060' type=UDP (UDP transport) 16:14:15.549 pjsua_core.c TX 381 bytes Request msg REGISTER/cseq=27259 (tdta0x86c95f8) to UDP 78.23.84.212:5060: REGISTER sip:78.23.84.212 SIP/2.0 Via: SIP/2.0/UDP 78.23.84.212:5067;rport;branch=z9hG4bKPjRDge8YNh2Pf8PvmqOY9f8wjoe89xky5f