It first showed up in 23.0a1/20130427. The regression range is: http://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=a6104e0e5a2c&tochange=0e45f1b9521f It might be caused by http://hg.mozilla.org/mozilla-central/rev/7c244b521e54. Signature mozilla::dom::AudioContext::GetJSContext() More Reports Search UUID 874c3daf-8bad-452f-ac4f-8811e2130428 Date Processed 2013-04-28 18:43:08 Uptime 116 Last Crash more than 3 months before submission Install Age 1.9 minutes since version was first installed. Install Time 2013-04-28 18:41:00 Product Firefox Version 23.0a1 Build ID 20130428031010 Release Channel nightly OS Windows NT OS Version 6.1.7601 Service Pack 1 Build Architecture x86 Build Architecture Info GenuineIntel family 6 model 23 stepping 6 Crash Reason EXCEPTION_ACCESS_VIOLATION_READ Crash Address 0x0 App Notes AdapterVendorID: 0x1002, AdapterDeviceID: 0x9581, AdapterSubsysID: 30c5103c, AdapterDriverVersion: 8.850.0.0 D2D? D2D+ DWrite? DWrite+ D3D10 Layers? D3D10 Layers+ WebGL? EGL? EGL+ GL Context? GL Context+ WebGL+ Processor Notes sp-processor05.phx1.mozilla.com_19953:2012 EMCheckCompatibility True Adapter Vendor ID 0x1002 Adapter Device ID 0x9581 Total Virtual Memory 4294836224 Available Virtual Memory 3225526272 System Memory Use Percentage 71 Available Page File 4983857152 Available Physical Memory 1218576384 Frame Module Signature Source 0 xul.dll mozilla::dom::AudioContext::GetJSContext content/media/webaudio/AudioContext.cpp:353 1 xul.dll `mozilla::dom::ScriptProcessorNodeEngine::SendBuffersToMainThread'::`4'::Command content/media/webaudio/ScriptProcessorNode.cpp:293 2 xul.dll nsThread::ProcessNextEvent xpcom/threads/nsThread.cpp:627 3 xul.dll NS_ProcessNextEvent obj-firefox/xpcom/build/nsThreadUtils.cpp:238 4 xul.dll mozilla::ipc::MessagePump::Run ipc/glue/MessagePump.cpp:82 5 xul.dll MessageLoop::RunHandler ipc/chromium/src/base/message_loop.cc:212 6 xul.dll MessageLoop::Run ipc/chromium/src/base/message_loop.cc:186 7 xul.dll nsBaseAppShell::Run widget/xpwidgets/nsBaseAppShell.cpp:163 8 xul.dll nsAppShell::Run widget/windows/nsAppShell.cpp:113 9 xul.dll nsAppStartup::Run toolkit/components/startup/nsAppStartup.cpp:289 10 xul.dll XREMain::XRE_mainRun toolkit/xre/nsAppRunner.cpp:3879 11 xul.dll XREMain::XRE_main toolkit/xre/nsAppRunner.cpp:3946 12 xul.dll XRE_main toolkit/xre/nsAppRunner.cpp:4158 13 firefox.exe do_main browser/app/nsBrowserApp.cpp:271 14 firefox.exe wmain toolkit/xre/nsWindowsWMain.cpp:105 15 firefox.exe __tmainCRTStartup crtexe.c:552 16 kernel32.dll BaseThreadInitThunk 17 ntdll.dll __RtlUserThreadStart 18 ntdll.dll _RtlUserThreadStart More reports at: https://crash-stats.mozilla.com/report/list?signature=mozilla%3A%3Adom%3A%3AAudioContext%3A%3AGetJSContext%28%29