diff --git a/function/videv.py b/function/videv.py
index 16d6222..05cb17e 100644
--- a/function/videv.py
+++ b/function/videv.py
@@ -245,6 +245,9 @@ class videv_multistate(base):
             self.set(key, index == data)
             self.__tx__(key, self[key])
 
+    def __rx_functionality__(self, key, data):
+        pass    # read only device
+
 
 class videv_audio_player(base_routing):
     KEY_ACTIVE_PLAYER = 'player_%d'