USoundWave Will still be destory by gc after call AddToRoot

Development Programming & Scripting C++
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1

In UE5.3, I use RuntimeAudioImporter to load a wav file, which returns a USoundWave object. Due to the use of multithreading, I store it in a TQueue container. Since this container cannot be marked with UPROPERTY, it may cause the USoundWave to be released due to GC. Therefore, I called AddToRoot as soon as possible. However, I found that manually calling CollectGarbage(RF_NoFlags); still causes the USoundWave to be released. But when I stored the USoundWave in a TArray marked with UPROPERTY and called CollectGarbage(RF_NoFlags);, I found that the object was retained. Is this a bug? How can I prevent the USoundWave from being released by the GC system without marking UPROPERTY?

.h
UCLASS()
class AUDIOTEST_API AMyClass : public AActor
{
	GENERATED_BODY()
        ...
    UFUNCTION()
	void OnImportFinish(URuntimeAudioImporterLibrary* importerObject, UImportedSoundWave* ImportedSoundWave, ERuntimeImportStatus Status);

	TQueue<UImportedSoundWave*> Queue_Sounds;

	UPROPERTY()
	TArray<UImportedSoundWave*> Array_Sounds;
        ...
};



.cpp
void AMyClass::OnImportFinish(URuntimeAudioImporterLibrary* importerObject, UImportedSoundWave* ImportedSoundWave, ERuntimeImportStatus Status)
{
	GEngine->AddOnScreenDebugMessage(-1,10,FColor::Red, __func__);

	// the sound will still be garbage collected 
	ImportedSoundWave->AddToRoot();
	Queue_Sounds.Enqueue(ImportedSoundWave);

	// no garbage collected
	Array_Sounds.Add(ImportedSoundWave);
}
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create protected object before background thread, and on the background thread assign it, read more How to properly work with UObjects in background threads (GC) | Georgy's Tech Blog