HTML5 Audio API stop a sound triggered with noteGrainOn -

is there way stop (or forever pause) sound played ..

audiosource.notegrainon(when, starthere, duration_sound);

..before "duration_sound" variable stops it? via noteoff, how used?

yes. (note should use .start() - noteon() , notegrainon() deprecated.)

just call

audiosource.stop( 0 );

to stop immediately, or can schedule stop before sound finished playing calling

audiosource.stop( whentostop );

Live