         
         if holdMode && monoMode {
            toggleMonoKeyHeld(key)
-
+           redisplayHeldKeys()
         } else if holdMode && !monoMode {
             toggleKeyHeld(key)
             
         } else {
             turnOffKey(key)
         }
-        
-        lastKey = key
     }
     
     // *********************************************************

    @IBAction func keyPressed(sender: UIButton) {
        let key = sender
        
        if monoMode {
            if let lastKey = lastKey where lastKey != key {
                turnOffKey(lastKey)
            }
        }
        
        if holdMode {
            if midiNotesHeld.contains(midiNoteFromTag(key.tag)) {
                turnOffKey(key)

    func toggleMonoKeyHeld(key: UIButton) {
        if midiNotesHeld.contains(midiNoteFromTag(key.tag)) {
            midiNotesHeld.removeAll()
        } else {
            midiNotesHeld.removeAll()
            midiNotesHeld.append(midiNoteFromTag(key.tag))
        }
    }
    
