One more. When I compile, these messages scroll by in the output window:
[2019.08.21-11.17.12:731][997]LogClass: BreathingAudioClip HotReload.
[2019.08.21-11.17.12:734][997]LogHotReload: Re-instancing BreathingAudioComponent after hot-reload.
[2019.08.21-11.17.12:736][997]LogOutputDevice: Warning:
Script Stack (0 frames):
Ensure condition failed: bArchetypeReinstanced [File:/opt/unreal-engine-4.22/Engine/Source/Editor/UnrealEd/Private/Kismet2/KismetReinstanceUtilities.cpp] [Line: 1627]
Reinstancing non-actor (/Engine/Transient.World_1:PersistentLevel.MyActor_C_0.Audio); failed to resolve archetype object - property values may be lost.
Yes, dear error message, indeed, the property values are lost. But what I do against it?