Using sine waves especially cause excessive clicking and popping

See: https://dsp.stackexchange.com/questions/971/how-to-create-a-sine-wave-generator-that-can-smoothly-transition-between-frequen

• Phase accumulator
• Postprocess, detect changes above threshold and perform a linear transition

Tried:

• Scaling down amplitudes on end-of-notes during MIDI synthesis, didn't work well