     ///   - portID:          MIDI Unique Port ID
     ///   - offset:          the offset in samples that this event occurs in the buffer
     ///
-    public func receivedMIDIPitchWheel(_ pitchWheelValue: MIDIWord,
+    open func receivedMIDIPitchWheel(_ pitchWheelValue: MIDIWord,
                                        channel: MIDIChannel,
                                        portID: MIDIUniqueID?,
                                        offset: MIDITimeStamp) {

    /// - portID:     MIDI Unique Port ID
    /// - offset:     the offset in samples that this event occurs in the buffer
    ///
    public func receivedMIDISystemCommand(_ data: [MIDIByte],
                                          portID: MIDIUniqueID?,
                                          offset: MIDITimeStamp) {
        // Do nothing
    }

    /// MIDI Setup has changed
    public func receivedMIDISetupChange() {
        // Do nothing
    }

    /// MIDI Object Property has changed
    public func receivedMIDIPropertyChange(propertyChangeInfo: MIDIObjectPropertyChangeNotification) {
        // Do nothing
    }

    /// Generic MIDI Notification
    public func receivedMIDINotification(notification: MIDINotification) {
        // Do nothing
    }


    ///   - portID:   MIDI Unique Port ID
    ///   - offset:   the offset in samples that this event occurs in the buffer
    ///
    open func receivedMIDIAftertouch(_ pressure: MIDIByte,
                                       channel: MIDIChannel,
                                       portID: MIDIUniqueID?,
                                       offset: MIDITimeStamp) {
