OscillatorSourceでstopを呼ぶ前に複数回startを入れてもエラーにならないように変更 Change OscillatorSource. That can call start method more than once before stop method call. 
OscillatorSourceでstopを呼ぶ前に複数回startを入れてもエラーにならないように変更
Change OscillatorSource. That can call start method more than once before stop method call. 
h10x64/snd.js,h10x64/snd.js