Fix C++ Crash (Double free / Memory related)

I need a C++ expert to assist me in finding and fixing a very tricky, memory-related crash in a C++ library. It uses OMP, multiple threads, and tr1::shared_ptr's. I have tried many simple solutions (mutexes, better protection of certain things), but none have solved the problem so far. Ideally, you can help me profile & analyze things with Valgrind (or similar tools), to quickly track down where the problem is happening. I will be happy to help you get the library building, and help you trigger the crash. It *occasionally* crashes with the following error: ---- Unhandled Exception: Stack Trace ---- #0 0x00007fffde6fa44a in juce::AudioSampleBuffer::getNumSamples (this=0x30) at /usr/include/libopenshot-audio/JuceLibraryCode/modules/juce_audio_basics/buffers/juce_AudioSampleBuffer.h:121 #1 0x00007fffde767d19 in openshot::Frame::GetAudioSamplesCount (this=0x6fa93b0) at /home/jonathan/apps/libopenshot-git/src/[login to view URL] #2 0x00007fffde76eee8 in openshot::FrameMapper::GetFrame (this=0x626b2f0, requested_frame=3745) at /home/jonathan/apps/libopenshot-git/src/[login to view URL] #3 0x00007fffde719b2a in openshot::Clip::GetOrCreateFrame (this=0x6d12e60, number=3745) at /home/jonathan/apps/libopenshot-git/src/[login to view URL] #4 0x00007fffde717a0a in openshot::Clip::GetFrame (this=0x6d12e60, requested_frame=3745) at /home/jonathan/apps/libopenshot-git/src/[login to view URL] #5 0x00007fffde78a6ab in openshot::Timeline::GetFrame (this=0x190feb0, requested_frame=3745) at /home/jonathan/apps/libopenshot-git/src/[login to view URL]