diff --git a/alarmdecoder/decoder.py b/alarmdecoder/decoder.py
index 2a2c47f..ac2198c 100644
--- a/alarmdecoder/decoder.py
+++ b/alarmdecoder/decoder.py
@@ -367,7 +367,7 @@ class AlarmDecoder(object):
         if self._internal_address_mask & msg.mask > 0:
             self._update_internal_states(msg)
 
-        self.on_message(message=msg)
+            self.on_message(message=msg)
 
         return msg