diff --git a/Libraries/Opc.Ua.Server/Diagnostics/MonitoredNode.cs b/Libraries/Opc.Ua.Server/Diagnostics/MonitoredNode.cs
index 640052e78..8f5414a9e 100644
--- a/Libraries/Opc.Ua.Server/Diagnostics/MonitoredNode.cs
+++ b/Libraries/Opc.Ua.Server/Diagnostics/MonitoredNode.cs
@@ -294,13 +294,31 @@ public void OnMonitoredNodeChanged(ISystemContext context, NodeState node, NodeS
 
                     if (monitoredItem.AttributeId == Attributes.Value && (changes & NodeStateChangeMasks.Value) != 0)
                     {
-                        QueueValue(context, node, monitoredItem);
+                        ServerSystemContext serverSystemContext;
+                        if ((serverSystemContext = (context as ServerSystemContext)) != null)
+                        {
+                            ServerSystemContext context2 = serverSystemContext.Copy(new OperationContext(monitoredItem.Session, monitoredItem.DiagnosticsMasks));
+                            QueueValue(context2, node, monitoredItem);
+                        }
+                        else
+                        {
+                            QueueValue(context, node, monitoredItem);
+                        }
                         continue;
                     }
 
                     if (monitoredItem.AttributeId != Attributes.Value && (changes & NodeStateChangeMasks.NonValue) != 0)
                     {
-                        QueueValue(context, node, monitoredItem);
+                        ServerSystemContext serverSystemContext2;
+                        if ((serverSystemContext2 = (context as ServerSystemContext)) != null)
+                        {
+                            ServerSystemContext context3 = serverSystemContext2.Copy(new OperationContext(monitoredItem.Session, monitoredItem.DiagnosticsMasks));
+                            QueueValue(context3, node, monitoredItem);
+                        }
+                        else
+                        {
+                            QueueValue(context, node, monitoredItem);
+                        }
                         continue;
                     }
                 }