diff --git a/src/main/java/org/apache/sling/resource/presence/internal/ResourcePresenter.java b/src/main/java/org/apache/sling/resource/presence/internal/ResourcePresenter.java
index aa16cd1..f38cfe6 100644
--- a/src/main/java/org/apache/sling/resource/presence/internal/ResourcePresenter.java
+++ b/src/main/java/org/apache/sling/resource/presence/internal/ResourcePresenter.java
@@ -59,10 +59,10 @@
     private ServiceRegistration<ResourceChangeListener> listenerRegistration;
 
     @Reference
-    private ResourceResolverFactory resourceResolverFactory;
+    private volatile ResourceResolverFactory resourceResolverFactory;
 
     @Reference
-    private ServiceUserMapped serviceUserMapped;
+    private volatile ServiceUserMapped serviceUserMapped;
 
     private final Logger logger = LoggerFactory.getLogger(ResourcePresenter.class);