Change events to avoid multi-threading errors

speller.py

@@ -189,10 +189,13 @@ class Speller(wx.Frame):
     def OnKeyDown(self, event):
         keycode = event.GetKeyCode()
         event.Skip()
-        pub.sendMessage("listener", message="falling")
+        wx.CallAfter(self.Clicked)
 
     def Listener(self, message):
         if message == "falling":
+            wx.CallAtfer(self.Clicked)
+
+    def Clicked(self):
         if not self.running:
             self.running = True
             self.cycle = 0