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--- a/libupnpp/control/cdircontent.hxx
+++ b/libupnpp/control/cdircontent.hxx
@@ -64,6 +64,8 @@
     // The map keys are the XML tag names
     std::map<std::string, std::string> m_props;
 
+    // Resource URIs: there may be several, for example for different
+    // audio formats of the same track
     std::vector<UPnPResource> m_resources;
 
     /** Get named property
@@ -128,6 +130,12 @@
     std::vector<UPnPDirObject> m_containers;
     std::vector<UPnPDirObject> m_items;
 
+    void clear() 
+    { 
+        m_containers.clear();
+        m_items.clear();
+    }
+
     /**
      * Parse from DIDL-Lite XML data.
      *