Erratic behavior happens on my Yamaha S90ES, my Yamaha MX61, and my Instruo QPQ quantizer.
However, I just quickly tried Hermod with a MicroKORG, and there were no problems. Is it possible that Yamaha does something different? Is there any way you can try Hermod with a Yamaha?
As for the QPQ, I have no idea what’s going on. Maybe it’s similar to the Yamaha.
I just found this https://www.midi.org/forum/228-writing-midi-software-send-note-off,-or-zero-velocity-note-on
"From what I can find out online, most modern MIDI equipment (keyboards, controllers) sends Note On messages with a velocity of 0 to end a note, rather than Note Off messages as per the spec. IIUC this is to make it easier to send a complete sequence of notes using running status. "
“A receiver must be capable of recognizing either method of turning off a note, and should treat them identically.”
Is it possible that this is what’s going on? Is there any way you could create a test build of the app code that tries to do it the other way than how you have it, so I can see if that’s the problem here? Anything you can suggest would be helpful. I don’t have this problem with any other MIDI sequencer! (But of course, nothing else is quite like Hermod, either)