苹果最终非beta ios 11发布是否已知问题？ 我在哪里可以找到MRAVOutputContext参考？
来自Crashlytics崩溃报告:(崩溃时启动蓝牙音频时重现，但在调试时无法重现）
崩溃：com.apple.coremedia.routingcontext.xpc.notifications
EXC_BAD_ACCESS KERN_INVALID_ADDRESS 0x0000000fa4a1beb8
#23. Crashed: com.apple.coremedia.routingcontext.xpc.notifications
0 libobjc.A.dylib 0x1856f4430 objc_msgSend + 16
1 MediaRemote 0x191826618 -[MRAVOutputContext _outputDevicesDidChangeNotification:] + 296
2 CoreFoundation 0x18615e12c __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__ + 20
3 CoreFoundation 0x18615d6cc _CFXRegistrationPost + 420
4 CoreFoundation 0x18615d430 ___CFXNotificationPost_block_invoke + 60
5 CoreFoundation 0x1861da9f4 -[_CFXNotificationRegistrar find:object:observer:enumerator:] + 1408
6 CoreFoundation 0x1860943e0 _CFXNotificationPost + 380
7 Foundation 0x186ab1498 -[NSNotificationCenter postNotificationName:object:userInfo:] + 68
8 AVFoundation 0x18ba5beb4 AVCMNotificationDispatcherCallback + 200
9 CoreFoundation 0x18615e12c __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__ + 20
10 CoreFoundation 0x18615d6cc _CFXRegistrationPost + 420
11 CoreFoundation 0x18615d430 ___CFXNotificationPost_block_invoke + 60
12 CoreFoundation 0x1861da9f4 -[_CFXNotificationRegistrar find:object:observer:enumerator:] + 1408
13 CoreFoundation 0x1860943e0 _CFXNotificationPost + 380
14 CoreFoundation 0x1860b758c CFNotificationCenterPostNotification + 132
15 CoreMedia 0x1892c6114 CMNotificationCenterPostNotification + 124
16 CoreMedia 0x1893c6828 __figXPC_HandleNotificationMessage_block_invoke + 164
17 libdispatch.dylib 0x185b51088 _dispatch_call_block_and_release + 24
18 libdispatch.dylib 0x185b51048 _dispatch_client_callout + 16
19 libdispatch.dylib 0x185b5ae48 _dispatch_queue_serial_drain$VARIANT$mp + 528
20 libdispatch.dylib 0x185b5b7d8 _dispatch_queue_invoke$VARIANT$mp + 340
21 libdispatch.dylib 0x185b5c200 _dispatch_root_queue_drain_deferred_wlh$VARIANT$mp + 400
22 libdispatch.dylib 0x185b644a0 _dispatch_workloop_worker_thread$VARIANT$mp + 644
23 libsystem_pthread.dylib 0x185df6fe0 _pthread_wqthread + 932
更新：已在官方发布中修复