On Tue, Aug 30, 2016 at 11:03 AM, Vincent Vanbesien (DIEHCO) <electronique@diehco.com> wrote:

Finally, the problem seems come from the vst~ that miss some event when releasing (note 0) (but also sometimes when pushing). It is easy to reproduce pushing only 2 keys. I understand that the VST plugin instrument stay in sustain period until receiving again the note 0. I tried with different plugins.

Note 0 doesn't release, it does something with note 0 depending on what velocity it comes with.A
MIDI note on message is three bytes long: note-on status (144 + channel number), note number (0-127), and velocity (0-127).
To turn a note off you can either send a note-on message with velocity zero, or send a note-off message: status (128+channel number), note number (0-127), velocity (0-127).
Another issue to be aware of is "running status", where the status byte is only sent once as long as it doesn't change, followed by a series of note-number, velocity pairs.

Martin