ok seen this crashing at a boot loop
09-28 18:21:50.496 3684 3684 E AndroidRuntime: *** FATAL EXCEPTION IN SYSTEM PROCESS: main
09-28 18:21:50.496 3684 3684 E AndroidRuntime: java.lang.RuntimeException: Failed to create service com.android.server.media.MediaSessionService: service constructor threw an exception
09-28 18:21:50.496 3684 3684 E AndroidRuntime: at com.android.server.SystemServiceManager.startService(SystemServiceManager.java:113)
09-28 18:21:50.496 3684 3684 E AndroidRuntime: at com.android.server.SystemServer.startOtherServices(SystemServer.java:1741)
09-28 18:21:50.496 3684 3684 E AndroidRuntime: at com.android.server.SystemServer.run(SystemServer.java:529)
09-28 18:21:50.496 3684 3684 E AndroidRuntime: at com.android.server.SystemServer.main(SystemServer.java:356)
09-28 18:21:50.496 3684 3684 E AndroidRuntime: at java.lang.reflect.Method.invoke(Native Method)
09-28 18:21:50.496 3684 3684 E AndroidRuntime: at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:491)
09-28 18:21:50.496 3684 3684 E AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:918)
09-28 18:21:50.496 3684 3684 E AndroidRuntime: Caused by: java.lang.reflect.InvocationTargetException
09-28 18:21:50.496 3684 3684 E AndroidRuntime: at java.lang.reflect.Constructor.newInstance0(Native Method)
09-28 18:21:50.496 3684 3684 E AndroidRuntime: at java.lang.reflect.Constructor.newInstance(Constructor.java:343)
09-28 18:21:50.496 3684 3684 E AndroidRuntime: at com.android.server.SystemServiceManager.startService(SystemServiceManager.java:102)
09-28 18:21:50.496 3684 3684 E AndroidRuntime: ... 6 more
09-28 18:21:50.496 3684 3684 E AndroidRuntime: Caused by: java.lang.LinkageError: While checking class com.android.server.media.MediaSessionService$SessionManagerImpl method void com.android.server.media.MediaSessionService$SessionManagerImpl.notifySession2Created(android.media.Session2Token) signature against superclass android.media.session.ISessionManager$Stub: Failed to resolve arg 0 type android.media.Session2Token with dalvik.system.PathClassLoader (declaration of 'com.android.server.media.MediaSessionService$SessionManagerImpl' appears in /system/framework/services.jar)
09-28 18:21:50.496 3684 3684 E AndroidRuntime: at com.android.server.media.MediaSessionService.<init>(MediaSessionService.java:155)
09-28 18:21:50.496 3684 3684 E AndroidRuntime: ... 9 more
09-28 18:21:50.496 3684 3684 E AndroidRuntime: Caused by: java.lang.NoClassDefFoundError: Failed resolution of: Landroid/media/Session2Token;
09-28 18:21:50.496 3684 3684 E AndroidRuntime: ... 10 more
09-28 18:21:50.496 3684 3684 E AndroidRuntime: Caused by: java.lang.ClassNotFoundException: android.media.Session2Token
09-28 18:21:50.496 3684 3684 E AndroidRuntime: ... 10 more
09-28 18:21:50.498 3684 3684 I am_crash: [3684,0,system_server,-1,java.lang.ClassNotFoundException,android.media.Session2Token,MediaSessionService.java,155]