Hi Benny Hi all I just tried latest svn trunk 3404 on 2 different Mac with coreaudio enabled. On Mac mini it seams to work. On Mac book it crashes when connecting call to conference room. I have set the conference room to 48000Hz, Stereo and make or receive a G711 call with 8000 Hz, Mono. When adding the call to the room pjmedia crashes here: Exception Type: EXC_CRASH (SIGABRT) Exception Codes: 0x0000000000000000, 0x0000000000000000 Crashed Thread: 8 Application Specific Information: Assertion failed: (*ioNumberDataPackets == strm->resample_buf_count), function resampleProc, file ../src/pjmedia-audiodev/coreaudio_dev.c, line 658. Tell me if you need more information. Regards Michael