Extraneous MIDI from Logic Pro X [128 123 64] messages

1

I’m wondering if anyone else can reproduce this since it seems unusual, and possibly a bug in Logic Pro X or the Core Audio MIDI classes?

I added the sample logging code from the MidiBuffer documentation to the MultiOutSynth example i.e.

    void processBlock (AudioBuffer<float>& buffer, MidiBuffer& midiBuffer) override
    {
        for (const MidiMessageMetadata metadata : midiBuffer)
            if (metadata.numBytes == 3)
                Logger::writeToLog (metadata.getMessage().getDescription());
...
  1. On intialisation, Logic Pro X sends a bunch of initial messages, they all make sense (RPN resets etc).
  2. Then I play a note and the note on and off make sense
  3. Switch Logic Pro X in to the background (back to Xcode) and it sends a bunch of note-offs

This is what I get

Controller Registered Parameter (fine): 4 Channel 1
Controller Registered Parameter (coarse): 0 Channel 1
Controller Data Entry (coarse): 0 Channel 1
Controller Registered Parameter (fine): 3 Channel 1
Controller Registered Parameter (coarse): 0 Channel 1
Controller Data Entry (coarse): 0 Channel 1
[... etc repeated for each channel ...]

[play a note]
Note on C3 Velocity 98 Channel 1
Note off C3 Velocity 64 Channel 1

[switch to background back to Xcode]
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1
Note off D#8 Velocity 64 Channel 1

Those note-offs are data [128 123 64]. That “123” has a certain whiff since it’s the CC# for “all notes off”.

Any ideas?

2

I just gave this a go with both the AudioPluginDemo, and with the MultiOutSynthPlugin. In both cases, I see some controller and sysex messages sent after initialisting the plugin instance, but I don’t see any [128 123 64] messages when switching between applications.

I tested with the AU versions of these plugins. Are you using AU, or AUv3? Also, which Logic version are you using?

Is there anything else notable about your setup, such as specific midi controllers or drivers? Does the issue happen every time you switch between apps?

You could try sticking a breakpoint or some logging in HandleMidiEvent in juce_AU_Wrapper.mm to check whether the strange events are coming from Logic, or being added accidentally somewhere in the AU wrapper. If you see the D#8 note-off events in HandleMidiEvent, then the issue is likely somewhere in Logic.

3

Thanks for the quick response. I already saw the messages coming from the HandleMidiEvent callback from the Core Audio classes, rather than the JUCE AU wrapper. I’m on Logic 10.4.6, just AU (not v3), with this check. I’m not aware of anything unusual installed and have no external controllers connected during this check. I’ll check whether it’s switching between any apps, or just the Logic > Xcode transition. And delve in to see if I have any unusual drivers

4

It could be a bug in that Logic version. I was testing with 10.6.1 and didn’t see any similar issues.

5

I’ll grab 10.6.1 now! Thanks