Oh this is fun, love audio toys! I'm noticing when I add two notes somewhat close together the audio pops. Also when you tab away I think the tab just slows way down bc I think it has stopped playing but then out of nowhere I hear a note haha! You might also be interested in this, was really helpful for me when I was messing around w/ writing my own ADSR real-time synth stuff in Unity https://pages.mtu.edu/~suits/NoteFreqCalcs.html