diff --git a/src/PepperDash.Essentials.Core/Routing/Extensions.cs b/src/PepperDash.Essentials.Core/Routing/Extensions.cs
index f7b235ae..b3c02e4e 100644
--- a/src/PepperDash.Essentials.Core/Routing/Extensions.cs
+++ b/src/PepperDash.Essentials.Core/Routing/Extensions.cs
@@ -143,7 +143,7 @@ namespace PepperDash.Essentials.Core
         {
             try
             {
-                Debug.LogMessage(LogEventLevel.Information, "Release route for '{destination}':'{inputPortKey}'", destination?.Key ?? "", string.IsNullOrEmpty(inputPortKey) ? "auto" : inputPortKey);
+                Debug.LogMessage(LogEventLevel.Information, "Release route for '{destination}':'{inputPortKey}'", destination?.Key ?? null, string.IsNullOrEmpty(inputPortKey) ? "auto" : inputPortKey);
 
                 if (RouteRequests.TryGetValue(destination.Key, out RouteRequest existingRequest) && destination is IWarmingCooling)
                 {
@@ -162,7 +162,7 @@ namespace PepperDash.Essentials.Core
                 }
             } catch (Exception ex)
             {
-                Debug.LogMessage(ex, "Exception releasing route for '{destination}':'{inputPortKey}'",null, destination?.Key ?? "", string.IsNullOrEmpty(inputPortKey) ? "auto" : inputPortKey);
+                Debug.LogMessage(ex, "Exception releasing route for '{destination}':'{inputPortKey}'",null, destination?.Key ?? null, string.IsNullOrEmpty(inputPortKey) ? "auto" : inputPortKey);
             }
         }
 
diff --git a/src/PepperDash.Essentials.Core/Routing/RouteDescriptorCollection.cs b/src/PepperDash.Essentials.Core/Routing/RouteDescriptorCollection.cs
index d058872e..51d0aa4b 100644
--- a/src/PepperDash.Essentials.Core/Routing/RouteDescriptorCollection.cs
+++ b/src/PepperDash.Essentials.Core/Routing/RouteDescriptorCollection.cs
@@ -53,14 +53,14 @@ namespace PepperDash.Essentials.Core
         /// <returns>null if no RouteDescriptor for a destination exists</returns>
         public RouteDescriptor GetRouteDescriptorForDestination(IRoutingInputs destination)
         {
-            Debug.LogMessage(LogEventLevel.Information, "Getting route descriptor for '{destination}'", destination?.Key ?? "");
+            Debug.LogMessage(LogEventLevel.Information, "Getting route descriptor for '{destination}'", destination?.Key ?? null);
 
             return RouteDescriptors.FirstOrDefault(rd => rd.Destination == destination);
         }
 
         public RouteDescriptor GetRouteDescriptorForDestinationAndInputPort(IRoutingInputs destination, string inputPortKey)
         {
-            Debug.LogMessage(LogEventLevel.Information, "Getting route descriptor for '{destination}':'{inputPortKey}'", destination?.Key ?? "", string.IsNullOrEmpty(inputPortKey) ? "auto" : inputPortKey);
+            Debug.LogMessage(LogEventLevel.Information, "Getting route descriptor for '{destination}':'{inputPortKey}'", destination?.Key ?? null, string.IsNullOrEmpty(inputPortKey) ? "auto" : inputPortKey);
             return RouteDescriptors.FirstOrDefault(rd => rd.Destination == destination && rd.InputPort != null && rd.InputPort.Key == inputPortKey);
         }
 
@@ -70,7 +70,7 @@ namespace PepperDash.Essentials.Core
         /// </summary>
         public RouteDescriptor RemoveRouteDescriptor(IRoutingInputs destination, string inputPortKey = "")
         {
-            Debug.LogMessage(LogEventLevel.Information, "Removing route descriptor for '{destination}':'{inputPortKey}'", destination.Key ?? "", string.IsNullOrEmpty(inputPortKey) ? "auto" : inputPortKey);
+            Debug.LogMessage(LogEventLevel.Information, "Removing route descriptor for '{destination}':'{inputPortKey}'", destination.Key ?? null, string.IsNullOrEmpty(inputPortKey) ? "auto" : inputPortKey);
 
             var descr = string.IsNullOrEmpty(inputPortKey) 
                 ? GetRouteDescriptorForDestination(destination)