diff --git a/essentials-framework/Essentials DM/Essentials_DM/Endpoints/Receivers/DmRmcHelper.cs b/essentials-framework/Essentials DM/Essentials_DM/Endpoints/Receivers/DmRmcHelper.cs
index bb8aec65..57f522fd 100644
--- a/essentials-framework/Essentials DM/Essentials_DM/Endpoints/Receivers/DmRmcHelper.cs	
+++ b/essentials-framework/Essentials DM/Essentials_DM/Endpoints/Receivers/DmRmcHelper.cs	
@@ -436,9 +436,9 @@ namespace PepperDash.Essentials.DM
                 }
                 return rx;
             }
-            else if (parentDev is DmChassisController)
+            else if (parentDev is IDmSwitchWithEndpointOnlineFeedback)
             {
-                var controller = parentDev as DmChassisController;
+                var controller = parentDev as IDmSwitchWithEndpointOnlineFeedback;
                 var chassis = controller.Chassis;
                 var num = props.ParentOutputNumber;
                 Debug.Console(1, "Creating DM Chassis device '{0}'. Output number '{1}'.", key, num);
diff --git a/essentials-framework/Essentials DM/Essentials_DM/Endpoints/Transmitters/DmTxHelpers.cs b/essentials-framework/Essentials DM/Essentials_DM/Endpoints/Transmitters/DmTxHelpers.cs
index 84007032..140f0f45 100644
--- a/essentials-framework/Essentials DM/Essentials_DM/Endpoints/Transmitters/DmTxHelpers.cs	
+++ b/essentials-framework/Essentials DM/Essentials_DM/Endpoints/Transmitters/DmTxHelpers.cs	
@@ -127,10 +127,10 @@ namespace PepperDash.Essentials.DM
             BasicDmTxControllerBase tx;
             bool useChassisForOfflineFeedback = false;
 
-            if (parentDev is DmChassisController)
+            if (parentDev is IDmSwitchWithEndpointOnlineFeedback)
             {
                 // Get the Crestron chassis and link stuff up
-                var switchDev = (parentDev as DmChassisController);
+                var switchDev = (parentDev as IDmSwitchWithEndpointOnlineFeedback);
                 var chassis = switchDev.Chassis;
 
                 //Check that the input is within range of this chassis' possible inputs
@@ -179,6 +179,7 @@ namespace PepperDash.Essentials.DM
                     return null;
                 }
             }
+
             if (parentDev is DmpsRoutingController)
             {
                 // Get the DMPS chassis and link stuff up