diff --git a/platypush/backend/music/mopidy.py b/platypush/backend/music/mopidy.py
index c41b2da960..66bf5ad54c 100644
--- a/platypush/backend/music/mopidy.py
+++ b/platypush/backend/music/mopidy.py
@@ -196,7 +196,7 @@ class MusicMopidyBackend(Backend):
         return hndl
 
     def _on_error(self):
-        def hndl(error):
+        def hndl(ws, error):
             self.logger.warning('Mopidy websocket error: {}'.format(error))
         return hndl
 
diff --git a/platypush/backend/todoist.py b/platypush/backend/todoist.py
index 15797345f0..aca190208f 100644
--- a/platypush/backend/todoist.py
+++ b/platypush/backend/todoist.py
@@ -59,7 +59,8 @@ class TodoistBackend(Backend):
         return hndl
 
     def _on_error(self):
-        def hndl(error):
+        # noinspection PyUnusedLocal
+        def hndl(ws, error):
             self.logger.warning('Todoist websocket error: {}'.format(error))
         return hndl