diff --git a/qtgui/items.py b/qtgui/items.py
index cf52962..73785cc 100644
--- a/qtgui/items.py
+++ b/qtgui/items.py
@@ -261,7 +261,7 @@ class Note(_EventTraits, QtWidgets.QGraphicsRectItem): #resolution order is impo
             else:
                 self.duringDurationChange = False #if we don't reset here a note will not be movable after a single click on the edge area            
 
-    def mouseReleaseEvent(self):
+    def mouseReleaseEvent(self, event):
         super().mouseReleaseEvent(event)
         self.duringDurationChange = False