Same here.. Exception Codes: 0x0000000000000001, 0x00000001aba87c34 Termination Reason: SIGNAL 5 Trace/BPT trap: 5 Terminating Process: exc handler [4363] Triggered by Thread: 12 Last Exception Backtrace: 0 CoreFoundation 0x1a3bbeb28 __exceptionPreprocess + 164 (NSException.m:249) 1 libobjc.A.dylib 0x19ba36f78 objc_exception_throw + 60 (objc-exception.mm:356) 2 CoreAutoLayout 0x1c4b5765c _AssertAutoLayoutOnAllowedThreadsOnly + 328 (NSISEngine.m:0) 3 CoreAutoLayout 0x1c4b5da70 -[NSISEngine _optimizeWithoutRebuilding] + 72 (NSISEngine.m:1716) 4 CoreAutoLayout 0x1c4b5d784 -[NSISEngine optimize] + 96 (NSISEngine.m:1690) 5 CoreAutoLayout 0x1c4b5d510 -[NSISEngine performPendingChangeNotifications] + 104 (NSISEngine.m:684) 6 UIKitCore 0x1a5d813c8 -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 2248 (UIView.m:20093) 7 QuartzCore 0x1a51abe30 CA::Layer::layout_if_needed(CA::Transaction*) + 504 (CALayer.mm:10816) 8 QuartzCore 0x1a51ab9b4 CA::Layer::layout_and_display_if_needed(CA::Transaction*) + 148 (CALayer.mm:2598) 9 QuartzCore 0x1a51b1bb4 CA::Context::commit_transaction(CA::Transaction*, double, double*) + 464 (CAContextInternal.mm:2760) 10 QuartzCore 0x1a51ab1bc CA::Transaction::commit() + 648 (CATransactionInternal.mm:432) 11 QuartzCore 0x1a533fee4 CA::Transaction::release_thread(void*) + 228 (CATransactionInternal.mm:636) 12 libsystem_pthread.dylib 0x1ffabdb8c _pthread_tsd_cleanup + 620 (pthread_tsd.c:416) 13 libsystem_pthread.dylib 0x1ffab7f84 _pthread_exit + 84 (pthread.c:1766) 14 libsystem_pthread.dylib 0x1ffab9854 _pthread_wqthread_exit + 64 (pthread.c:2625) 15 libsystem_pthread.dylib 0x1ffab4fa8 _pthread_wqthread + 424 (pthread.c:2659) 16 libsystem_pthread.dylib 0x1ffab4fc0 start_wqthread + 8 (:-1) ... hread 12 Crashed: 0 libsystem_c.dylib 0x00000001aba87c34 __abort + 168 (abort.c:171) 1 libsystem_c.dylib 0x00000001aba87b8c abort + 192 (abort.c:126) 2 libc++abi.dylib 0x00000001ff9d8ccc abort_message + 132 (abort_message.cpp:78) 3 libc++abi.dylib 0x00000001ff9c8e84 demangling_terminate_handler() + 348 (cxa_default_handlers.cpp:77) 4 libobjc.A.dylib 0x000000019ba3a0bc _objc_terminate() + 144 (objc-exception.mm:496) 5 libc++abi.dylib 0x00000001ff9d8090 std::__terminate(void (*)()) + 16 (cxa_handlers.cpp:59) 6 libc++abi.dylib 0x00000001ff9db2e4 __cxxabiv1::failed_throw(__cxxabiv1::__cxa_exception*) + 88 (cxa_exception.cpp:152) 7 libc++abi.dylib 0x00000001ff9db228 __cxa_throw + 308 (cxa_exception.cpp:283) 8 libobjc.A.dylib 0x000000019ba370e0 objc_exception_throw + 420 (objc-exception.mm:385) 9 CoreAutoLayout 0x00000001c4b5765c _AssertAutoLayoutOnAllowedThreadsOnly + 328 (NSISEngine.m:0) 10 CoreAutoLayout 0x00000001c4b5da70 -[NSISEngine _optimizeWithoutRebuilding] + 72 (NSISEngine.m:1716) 11 CoreAutoLayout 0x00000001c4b5d784 -[NSISEngine optimize] + 96 (NSISEngine.m:1690) 12 CoreAutoLayout 0x00000001c4b5d510 -[NSISEngine performPendingChangeNotifications] + 104 (NSISEngine.m:684) 13 UIKitCore 0x00000001a5d813c8 -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 2248 (UIView.m:20093) 14 QuartzCore 0x00000001a51abe30 CA::Layer::layout_if_needed(CA::Transaction*) + 504 (CALayer.mm:10816) 15 QuartzCore 0x00000001a51ab9b4 CA::Layer::layout_and_display_if_needed(CA::Transaction*) + 148 (CALayer.mm:2598) 16 QuartzCore 0x00000001a51b1bb4 CA::Context::commit_transaction(CA::Transaction*, double, double*) + 464 (CAContextInternal.mm:2760) 17 QuartzCore 0x00000001a51ab1bc CA::Transaction::commit() + 648 (CATransactionInternal.mm:432) 18 QuartzCore 0x00000001a533fee4 CA::Transaction::release_thread(void*) + 228 (CATransactionInternal.mm:636) 19 libsystem_pthread.dylib 0x00000001ffabdb8c _pthread_tsd_cleanup + 620 (pthread_tsd.c:416) 20 libsystem_pthread.dylib 0x00000001ffab7f84 _pthread_exit + 84 (pthread.c:1766) 21 libsystem_pthread.dylib 0x00000001ffab9854 _pthread_wqthread_exit + 64 (pthread.c:2625) 22 libsystem_pthread.dylib 0x00000001ffab4fa8 _pthread_wqthread + 424 (pthread.c:2659) 23 libsystem_pthread.dylib 0x00000001ffab4fc0 start_wqthread + 8 (:-1)

Did you find any solution? I had to have another buffer enqueued every second to circumvent this symptom.