Unreal Engine Issues
Unreal Engine Issues
Assertion failed in FAudioDevice::UnregisterSoundClass when GC
UE - Audio - Aug 13, 2018The licensee reported that check(IsInAudioThread()) was failed in FAudioDevice::UnregisterSoundClass when GC. The following is the call stack: 1 #00 pc 030d7b58 libUE4.so HandleError (/home/pirates ...
Crash when a floor mesh is removed while a Vehicle has SimulatePhysics disabled
UE - Runtime - Character - Sep 1, 2026When SimulatePhysics is disabled, the constraint update is skipped, so a reference to an invalid (already-removed) particle is left behind. As a workaround, the approach suggested by the licensee — ...
[PCG Mode] Tool actors spawned by PCG Editor Mode tools ignore the current level and are always created in the PersistentLevel
UE - Graphics Tools - PCG - Procedural Tools - Oct 21, 2026Summary In a non-World-Partition map with streamed sublevels, PCG Editor Mode interactive tools (Draw Spline / SpacingTool, Area, Paint, Volume, ...) spawn their new tool actor in the PersistentLevel ...
Ongoing D3D 'HUNG' crash in FD3D11DynamicRHI::GetQueryData
UE - Graphics Features - Jan 18, 2017This is a new ticket for the D3D 'HUNG' crash originally reported in [Link Removed]. Some fixes were introduced in 4.14.2 that decreased the occurrences of this crash, but other cases are still ongo ...
[CrashReport] UE4Editor_D3D11RHI!VerifyD3D11Result() [d3d11util.cpp:200]
UE - Editor - UI Systems - Slate - May 9, 2016This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Error message: Fatal error: [Link Removed] [Line: 200] SwapChain->ResizeBuffers(1,SizeX,SizeY ...
Chaos: geometry collection with One Way Interaction never breaks from its own collisions
UE - Runtime - Simulation - Aug 21, 2026A geometry collection with One Way Interaction Level set to 0 never breaks from its own collisions. It falls, lands, and stays intact no matter what it hits. Set the level to -1 (feature off) and ch ...
[Gauntlet] TestExecutor does not clean up or release devices when a test's StartTest returns false, causing device starvation or a deadlock with -NoTimeout
UE - QA - Tooling - Oct 21, 2026Summary When UnrealTestNode.StartTest returns false (or throws), TestExecutor.ExecuteTests moves the test straight to CompletedTests. It never calls CleanupTest or StopTest on the node, so the device ...
[CrashReport] UE4Editor_Renderer!FSceneRenderTargets::GetGBufferResourcesUniformBuffer() [scenerendertargets.h:408]
UE - Graphics Features - Jan 18, 2016This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below. Error message: Assertion failed: IsValidRef(GBuff ...
Crash caused by a race condition in Nanite::DispatchBasePass()
UE - Rendering - Features - Nanite - Feb 25, 2026Nanite::BuildShadingCommands() launches two asynchronous tasks: ShadingCommands.SetupTask ShadingCommands.BuildCommandsTask BuildCommandsTask is responsible for modifying ShadingCommands.Commands ...
[CrashReport] Linux crash - FLinuxSplashState::InitSplashResources()
UE - Platform - Linux - Oct 27, 2017This is a trending Linux crash in 4.18. It seems to occur before a project loads. Callstack from Log[2017.10.27-08.31.13:659][ 0]LogInit: - Physical RAM available (not considering process quota) ...