Sorry for the late answer, I was on Easter holidays. @RJ Ryan: I already considered the workaround after my last post here and got another error (last state before giving it up): Maximilians-MacBook-Air:mixxx DJMaxergy$ HOMEBREW_PATH=/usr/local Maximilians-MacBook-Air:mixxx DJMaxergy$ export CFLAGS="-I$HOMEBREW_PATH/include -I$HOMEBREW_PATH/include/opus -I/usr/local/include/opus -I/usr/local/opt/qt/include -I/usr/local/opt/openssl/include" Maximilians-MacBook-Air:mixxx DJMaxergy$ export CXXFLAGS="-I$HOMEBREW_PATH/include -I$HOMEBREW_PATH/include/opus -I/usr/local/include/opus -I/usr/local/opt/qt/include -I/usr/local/opt/openssl/include" Maximilians-MacBook-Air:mixxx DJMaxergy$ export LDFLAGS=-L$HOMEBREW_PATH/lib Maximilians-MacBook-Air:mixxx DJMaxergy$ scons stdlib=libc++ scons: Reading SConscript files ... INFO:root:Target Platform: osx INFO:root:Target Machine: x86_64 INFO:root:Build: debug INFO:root:Toolchain: gnu INFO:root:Crosscompile: NO INFO:root:Qt path: /usr/local/Cellar/qt@4/4.8.7_3 Automatically detecting Mac OS X SDK. XCode developer directory:/Applications/Xcode.app/Contents/Developer Found OS X SDK:macosx10.13 Automatically selected OS X SDK:/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk Checking whether the C++ compiler works... (cached) yes Configuring MixxxCore Configuring SoundTouch Configuring ReplayGain Configuring Ebur128Mit Checking for C library ebur128... (cached) no Checking for C library libebur128... (cached) no Checking for C header file sys/queue.h... (cached) yes Configuring PortAudio Checking for C library portaudio... (cached) yes Configuring PortMIDI Checking for C library porttime... (cached) no Checking for C library libporttime... (cached) no Checking for C header file porttime.h... (cached) yes Checking for C library portmidi... (cached) yes Checking for C header file portmidi.h... (cached) yes Configuring Qt Configuring TestHeaders Configuring FidLib Configuring SndFile Checking for C library sndfile... (cached) yes Checking whether SFC_SET_COMPRESSION_LEVEL is declared... (cached) yes Configuring FLAC Checking for C header file FLAC/stream_decoder.h... (cached) yes Checking for C library libFLAC... (cached) yes Configuring OggVorbis Checking for C library libvorbisfile... (cached) yes Checking for C library libvorbis... (cached) yes Checking for C library libogg... (cached) yes Checking for C library libvorbisenc... (cached) yes Configuring OpenGL Checking for C library GL... (cached) no Checking for C library opengl32... (cached) no Checking for C header file OpenGL/gl.h... (cached) yes Checking for C library GLU... (cached) no Checking for C library glu32... (cached) no Checking for C header file OpenGL/glu.h... (cached) yes Configuring TagLib Checking for C library tag... (cached) yes Configuring ProtoBuf Checking for C library libprotobuf-lite... (cached) yes Configuring Chromaprint Checking for C library chromaprint... (cached) yes Configuring RubberBand Checking for C library rubberband... (cached) yes Configuring SecurityFramework Configuring CoreServices Configuring IOKit Configuring QtScriptByteArray Configuring Reverb Configuring FpClassify Configuring PortAudioRingBuffer Configuring Mad Configuring CoreAudio Configuring MediaFoundation Configuring HSS1394 Configuring HID Configuring Bulk Configuring MacAppStoreException Configuring VinylControl Configuring LiveBroadcasting Checking for C library libshout... (cached) yes Configuring Opus Checking for C library opusfile... (cached) yes Configuring Profiling Configuring BuildTime Configuring QDebug Configuring Verbose Configuring Optimize Configuring FAAD Configuring WavPack Configuring ModPlug Configuring TestSuite Configuring Vamp Checking for C library vamp-hostsdk... (cached) yes Checking for vamp-plugin-sdk (2.7.1 or higher)... (cached) no Checking for C header file fftw3.h... (cached) yes Checking for C library fftw3... (cached) yes Configuring ColorDiagnostics Configuring Sanitizers Configuring LocaleCompare Configuring Battery Configuring UPower Configuring PerfTools Configuring AsmLib Configuring IPod Configuring FFMPEG Configuring OpenGLES Configuring QtKeychain Features Summary: ================ Mixxx Core Features... Enabled MAD MP3 Decoder... Disabled CoreAudio MP3/AAC Decoder... Enabled Media Foundation AAC Decoder Plugin... Disabled HSS1394 MIDI device support... Disabled HID controller support... Enabled USB Bulk controller support... Disabled Build for Mac App Store... Disabled Vinyl Control... Enabled Live Broadcasting Support... Enabled Opus (RFC 6716) support... Enabled profiling (e.g. gprof) support... Disabled Use __DATE__ and __TIME__... Enabled Debugging message output... Enabled Verbose compilation output... Disabled Optimization and Tuning... portable: sse2 CPU (>= Pentium 4) FAAD AAC audio file decoder plugin... Disabled WavPack audio file support plugin... Disabled Modplug module decoder plugin... Disabled Mixxx Test Suite... Disabled Vamp Analyzer support... Enabled Color Diagnostics... Disabled Clang Sanitizers (asan, ubsan, tsan, etc.)... Disabled Locale Aware Compare for SQLite... Disabled Battery meter support.... Enabled Google PerfTools... Disabled Agner Fog's ASMLIB... Disabled (due to debug build) NOT-WORKING iPod Support... Disabled FFmpeg/Avconv support... Disabled OpenGL-ES >= 2.0 support [Experimental]... Disabled Secure credentials storage support for Live Broadcasting profiles... Disabled ================ Building with flags: asan=0 battery=1 buildtime=1 bulk=0 color=0 coreaudio=1 faad=0 ffmpeg=0 hid=1 hss1394=0 ipod=0 localecompare=0 macappstore=0 mad=0 mediafoundation=0 modplug=0 opengles=0 optimize=portable opus=1 perftools=0 perftools_profiler=0 profiling=0 qdebug=1 qt_sqlite_plugin=0 qtkeychain=0 shoutcast=1 test=False tsan=0 ubsan=0 vamp=1 verbose=0 vinylcontrol=1 wv=0 Building with CC: gcc Building with CXX: g++ Building with CCFLAGS: -I/usr/local/include -I/usr/local/include/opus -I/usr/local/include/opus -I/usr/local/opt/qt/include -I/usr/local/opt/openssl/include -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk -mmacosx-version-min=10.8 -stdlib=libc++ -arch x86_64 -pipe -Wall -Wextra -g -F/usr/local/Cellar/qt@4/4.8.7_3/Frameworks -O3 -ffast-math -funroll-loops -fomit-frame-pointer -mtune=generic Building with CPPDEFINES: -Dx86_64 -DMIXXX_BUILD_DEBUG -DSETTINGS_FILE=\"mixxx.cfg\" -D__PORTAUDIO__ -DQT_TABLET_SUPPORT -DQT_SHARED -DQT_CORE_LIB -DQT_GUI_LIB -DQT_OPENGL_LIB -DQT_XML_LIB -DQT_SVG_LIB -DQT_SQL_LIB -DQT_SCRIPT_LIB -DQT_NETWORK_LIB -D__SNDFILE__ -DSFC_SUPPORTS_SET_COMPRESSION_LEVEL -D__COREAUDIO__ -D__HID__ -D__VINYLCONTROL__ -D__BROADCAST__ -D__OPUS__ -D__VAMP__ -Dkiss_fft_scalar=double -D__BATTERY__ Building with CXXFLAGS: -I/usr/local/include -I/usr/local/include/opus -I/usr/local/include/opus -I/usr/local/opt/qt/include -I/usr/local/opt/openssl/include -std=c++11 Building with LINKFLAGS: -L/usr/local/lib -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk -mmacosx-version-min=10.8 -stdlib=libc++ -Wl,-syslibroot,/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.13.sdk -arch x86_64 -framework QtCore -framework QtGui -framework QtOpenGL -framework QtXml -framework QtSvg -framework QtSql -framework QtScript -framework QtNetwork -framework QtTest -framework QtScriptTools -F/usr/local/Cellar/qt@4/4.8.7_3/Frameworks -L/usr/local/Cellar/qt@4/4.8.7_3/Frameworks -framework Security -framework CoreServices -framework IOKit -Wl,-headerpad,ffff -Wl,-headerpad_max_install_names Building with LIBS: portaudio portmidi sndfile libFLAC libvorbisfile libvorbis libogg libvorbisenc tag libprotobuf-lite chromaprint rubberband libshout opusfile vamp-hostsdk Building with PATH: /usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin ..... 14 warnings generated. [CC] lib/libebur128/ebur128/ebur128.c [CC] lib/portaudio/pa_ringbuffer.c [CXX] lib/qtscript-bytearray/bytearrayclass.cpp [CXX] lib/qtscript-bytearray/bytearrayprototype.cpp [MOC] lib/qtscript-bytearray/bytearrayclass.h [CXX] lib/qtscript-bytearray/moc_bytearrayclass.cc lib/qtscript-bytearray/moc_bytearrayclass.cc:13:2: error: "This file was generated using the moc from 4.8.7. It" #error "This file was generated using the moc from 4.8.7. It" ^ lib/qtscript-bytearray/moc_bytearrayclass.cc:14:2: error: "cannot be used with the include files from this version of Qt." #error "cannot be used with the include files from this version of Qt." ^ lib/qtscript-bytearray/moc_bytearrayclass.cc:15:2: error: "(The moc has changed too much.)" #error "(The moc has changed too much.)" ^ lib/qtscript-bytearray/moc_bytearrayclass.cc:47:7: error: unknown type name 'QMetaObjectExtraData' const QMetaObjectExtraData ByteArrayClass::staticMetaObjectExtraData = { ^ lib/qtscript-bytearray/moc_bytearrayclass.cc:47:44: error: no member named 'staticMetaObjectExtraData' in 'ByteArrayClass' const QMetaObjectExtraData ByteArrayClass::staticMetaObjectExtraData = { ~~~~~~~~~~~~~~~~^ lib/qtscript-bytearray/moc_bytearrayclass.cc:48:9: error: use of undeclared identifier 'qt_static_metacall' 0, qt_static_metacall ^ lib/qtscript-bytearray/moc_bytearrayclass.cc:62:39: error: incompatible operand types ('QDynamicMetaObjectData *' and 'const QMetaObject *') ...? QObject::d_ptr->metaObject : &staticMetaObject; ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~ 7 errors generated. scons: *** [lib/qtscript-bytearray/moc_bytearrayclass.o] Error 1 scons: building terminated because of errors. I will now try to reproduce the crash using the latest build as mentioned by @Be.