Unreal Engine Issues

Phaser module is malfunctioning

The phaser module that is part of the new Audio Engine causes audio from a Sound Cue to mute after playing for one second. The user states that the issue comes from the Phaser.cpp file producing a N ...

Rotational root motion accumulation to worldspace can add invalid translation

When a character is playing an animation that contains rotational root motion and that character is placed on a moving actor, an invalid translation component is introduced to the worldspace positio ...

Python crash the engine at exit.

A UDN reported various crashes at exit in the embedded Python library. I was able to repro the issue in Release-5.1 and trace it back at the point where python runs its garbage collection in Py_Fina ...

When duplicating the last point in a closed-loop spline, its metadata is inserted at the wrong index

The SplineComponentVisualizer allows users to alt+drag on a spline point to duplicate it. When this is done on the last point of a spline marked as "closed-loop", the new point is correctly added at ...

check(bRenderStateCreated) fires in SendRenderDynamicData_Concurrent called from FRegisterComponentContext::Process

FRegisterComponentContext::Process() in ActorComponent.cpp iterates over SendRenderDynamicDataPrimitives and calls SendRenderDynamicData_Concurrent() on each. The existing guard checks ::IsValid(Pri ...

[CrashReport] Access violation - FBlueprintCompilationManagerImpl::ReinstanceBatch

This is a trending crash in the 4.17 Preview. Unfortunately users have not provided any additional information. There is no record of this crash occurring in 4.16.2, so it is possibly a regression. ...

WP HLOD Crash on Small Cell Sizes

[CrashReport] UE4Editor-MetalRHI.dylib!FMetalDeviceContext::CreateDeviceContext()

Error message: SEGV_MAPERR at 0x3 Source Context: Most recent user affected CL: 3249277 Logs: [Link Removed] [Link Removed] [Link Removed] [Link Removed] CrashReporter User Descriptions:Just i ...

Physics Substepping doesn't have the same effect from 4.15 to 4.16

Physics Substepping doesn't have the same effect from 4.15 to 4.16. In 4.16+ the ponytail in the provided project will have a jitter effect even with substepping enabled. This is a regression: Work ...

Simulated ability tasks not being cleaned up in UActorChannel::ReplicationMap

I've noticed the issue occurring in both 4.20.3 (CL 4369336) and 4.21.0 (CL 4541578). The user on AnswerHub has also noticed the issue in 4.20.2 (CL unknown) and claims the issue did not occur in 4. ...