I want to use this codepen highcharts vu meter with mic input using getusermedia api for my apps, but never succeed to get in done : https://codepen.io/slatius/pen/BqblG?editors=1111

var buffer = context.createAudioBuffer(11025,100,0.2);

i'm not too good in javascript and runs out idea to fix it. it keeps throwing out this error when run :

Uncaught TypeError: context.createAudioBuffer is not a function

Maybe someone kind enough to help me solve this please?