Problem with sending and receiving large (INVITE) requests over TCP. The issue is documented in #1488. The solution is to try using port other than 5060 in both client and server, and/or reducing the SIP message size, as explained in Reducing SIP message size.
Please check this PJSUA2 section: Problems with Garbage Collection.
As reported in Android NDK forum, when shutting down OpenSLES sound device backend, it may block forever:
W/libOpenSLES(6434): frameworks/wilhelm/src/itf/IBufferQueue.c:57: pthread 0x5fce71c0 (tid 6670) sees object 0x5fcd0080 was locked by pthread 0x5f3a2cb0 (tid 6497) at frameworks/wilhelm/src/itf/IObject.c:411
Reported that audio quality recorded on the microphone is bad and the speed is
twice what it should be, it only happens on some devices. It could be fixed
by setting audio mode via
MODE_IN_COMMUNICATION in the
AudioManager am = (AudioManager) getSystemService(Context.AUDIO_SERVICE); int original_mode = am.getMode(); /* Set audio mode before using audio device, for example before making/answering a SIP call */ am.setMode(AudioManager.MODE_IN_COMMUNICATION); ... /* Restore back to the original mode after finished with audio device */ am.setMode(original_mode);