fix false positives for IsHMD on CAVE

Source/StudyFrameworkPlugin/Private/Help/SFUtils.cpp

@@ -143,6 +143,12 @@ bool FSFUtils::IsPrimary()
 
 bool FSFUtils::IsHMD()
 {
+	//the hack below seems not to work well on the CAVE (false positive), so first check whether we are on a cluster
+	if (IDisplayCluster::IsAvailable() && IDisplayCluster::Get().GetOperationMode() == EDisplayClusterOperationMode::Cluster)
+	{
+		return false;
+	}
+
 	// In editor builds: checks for EdEngine->IsVRPreviewActive()
 	// In packaged builds: checks for `-vr` in commandline or bStartInVR in UGeneralProjectSettings
 	return FAudioDevice::CanUseVRAudioDevice();