diff --git a/PepperDashEssentials/AppServer/MobileControlSystemController.cs b/PepperDashEssentials/AppServer/MobileControlSystemController.cs
index 08afb464..6c8dfe3e 100644
--- a/PepperDashEssentials/AppServer/MobileControlSystemController.cs
+++ b/PepperDashEssentials/AppServer/MobileControlSystemController.cs
@@ -52,7 +52,7 @@ namespace PepperDash.Essentials
 
         DateTime LastAckMessage;
 
-        public string SystemUuid;
+        public string SystemUuid { get; private set; }
 
 		List<MobileControlBridgeBase> RoomBridges = new List<MobileControlBridgeBase>();
 
diff --git a/PepperDashEssentials/AppServer/RoomBridges/MobileControlDdvc01RoomBridge.cs b/PepperDashEssentials/AppServer/RoomBridges/MobileControlDdvc01RoomBridge.cs
index eefd8fbc..2fc84d97 100644
--- a/PepperDashEssentials/AppServer/RoomBridges/MobileControlDdvc01RoomBridge.cs
+++ b/PepperDashEssentials/AppServer/RoomBridges/MobileControlDdvc01RoomBridge.cs
@@ -182,6 +182,10 @@ namespace PepperDash.Essentials.Room.MobileControl
 			/// 402
 			/// </summary>
 			public const uint ServerUrl = 402;
+            /// <summary>
+            /// 403
+            /// </summary>
+            public const uint QrCodeUrl = 403;
 			/// <summary>
 			/// 512
 			/// </summary>
@@ -907,6 +911,7 @@ namespace PepperDash.Essentials.Room.MobileControl
 			Debug.Console(1, this, "Server user code changed: {0}", UserCode);
 			EISC.StringInput[StringJoin.UserCodeToSystem].StringValue = UserCode;
 			EISC.StringInput[StringJoin.ServerUrl].StringValue = Parent.Config.ClientAppUrl;
+            EISC.StringInput[StringJoin.QrCodeUrl].StringValue = string.Format("http://{0}/api/system/{1}/qr", Parent.Config.ServerUrl, Parent.SystemUuid);
 		}
 	}
 }
\ No newline at end of file
diff --git a/essentials-framework/Essentials DM/Essentials_DM/Endpoints/Transmitters/DmTx4k202CController.cs b/essentials-framework/Essentials DM/Essentials_DM/Endpoints/Transmitters/DmTx4k202CController.cs
index fce45926..44fce36a 100644
--- a/essentials-framework/Essentials DM/Essentials_DM/Endpoints/Transmitters/DmTx4k202CController.cs	
+++ b/essentials-framework/Essentials DM/Essentials_DM/Endpoints/Transmitters/DmTx4k202CController.cs	
@@ -102,7 +102,15 @@ namespace PepperDash.Essentials.DM
             });
             AudioSourceNumericFeedback = new IntFeedback(() =>
             {
-                return (int)Tx.AudioSourceFeedback;
+                try
+                {
+                    return (int)Tx.AudioSourceFeedback;
+                }
+                catch
+                {
+                    return 0;
+                }
+
             });
 
             HdmiIn1HdcpCapabilityFeedback = new IntFeedback("HdmiIn1HdcpCapability", () =>