Replay crashing during playback

My replay is randomly crashing during playback. This has been happening consistently after upgrade to 4.13 . However , I cannot confirm this is the direct cause because there has been many code change. The crash will consistently produce this at the end of the output log.

Is there any way I can look or debug this further?

Attached is one of the crash log

link text

[2016.09.18-08.14.34:355][289]LogNetPackageMap:Warning: SerializeNewActor: Static actor failed to load: FullNetGuidPath: [107]/Game/PC_Maps/Playtest1/Playtest1.[105]Playtest1.[103]PersistentLevel.[229]Playtest1_C_1, Channel: 155
[2016.09.18-08.14.34:355][289]LogNet:Warning: UActorChannel::ProcessBunch: SerializeNewActor failed to find/spawn actor. Actor: NULL, Channel: 155
[2016.09.18-08.14.36:047][332]LogWindows:Error: === Critical error: ===
[2016.09.18-08.14.36:047][332]LogWindows:Error: 
[2016.09.18-08.14.36:047][332]LogWindows:Error: Fatal error!
[2016.09.18-08.14.36:047][332]LogWindows:Error: 
[2016.09.18-08.14.36:047][332]LogWindows:Error: Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x00000004