diff --git a/homeassistant/components/knx.py b/homeassistant/components/knx.py
index 8653f33c663..53c414922e4 100644
--- a/homeassistant/components/knx.py
+++ b/homeassistant/components/knx.py
@@ -136,8 +136,8 @@ class KNXGroupAddress(Entity):
             information relating to this device.
             """
             if (addr == self.state_address) or (addr == self.address):
-                self._state = data
-                self.update_ha_state()
+                self._state = data[0]
+                self.schedule_update_ha_state()
 
         KNXTUNNEL.register_listener(self.address, handle_knx_message)
         if self.state_address: