yeah something is wrong, I just tried to make the simplest of demos and I also can’t change velocity of the synth after a note has been played. Its really simple to test, I will post to answerhub bug section but if anyone else would like to confirm it try this. Create a blueprint with a synth component and synth preset variable. Enable inputs and have a keypress assigned to the synth’s “Note On” function. Enter an arbitrary note, I used 60, and a high velocity (100). Create another kepress function and have it play another note but with a low velocity (30, so you can still hear it).
Now what happens when you trigger one of the keypress it will be correct the first note, but then try the other keypress with the different velocity, it will have the same volume as the first keypress. Try it again but reverse the order and you should hear that the first note is correct and the second note played will match the first note’s velocity and not its’ own.
Maybe I am missing something but seems like a bug.