Утечка памяти в OfflineAudioContext

var audioCtx = new(window.AudioContext || window.webkitAudioContext)(); 
 
// define variables 
 
var play = document.querySelector('.play'); 
var stop = document.querySelector('.stop'); 
var progress = document.querySelector('#progress'); 
var buffer = document.querySelector('.buffer'); 
var myBuffer = null; 
 
var rendering = false; 
// use XHR to load an audio track, and 
// decodeAudioData to decode it and stick it in a buffer. 
// Then we put the buffer into the source 
 
function getData() { 
  request = new XMLHttpRequest(); 
 
  request.open('GET', 'https://s3-ap-northeast-1.amazonaws.com/storage.cowrite.decodeapps.io/Materials/Media/Audio/5a0aca5f35965-20171114-105007.mp3', true); 
 
  request.responseType = 'arraybuffer'; 
 
  request.onload = function() { 
    progress.innerText = 'loaded'; 
    var audioData = request.response; 
    audioCtx.decodeAudioData(audioData, function(buffer) { 
      myBuffer = buffer; 
 
      createBuffer(); 
    }).catch(function(err) { 
      console.log('Rendering failed: ' + err); 
      // Note: The promise should reject when startRendering is called a second time on an OfflineAudioContext 
    }); 
  } 
  request.send(); 
} 
buffer.setAttribute('disabled', 'disabled'); 
progress.innerText = 'loading...'; 
var cntRenfered = 0; 
 
function createBuffer() { 
  var offlineCtx = new OfflineAudioContext(2, myBuffer.length, myBuffer.sampleRate); 
  var source = offlineCtx.createBufferSource(); 
  source.buffer = myBuffer; 
  source.connect(offlineCtx.destination); 
  source.start(); 
  //source.loop = true; 
  offlineCtx.oncomplete = function(e) { 
    progress.innerText = 'completed'; 
    buffer.removeAttribute('disabled'); 
    source.disconnect(offlineCtx.destination); 
    cntRenfered++; 
    buffer.innerText = 'reCreateBuffer ' + cntRenfered; 
  } 
  offlineCtx.startRendering(); 
} 
 
buffer.onclick = function() { 
  progress.innerText = 'rendering...'; 
  buffer.setAttribute('disabled', 'disabled'); 
  createBuffer(); 
} 
 
getData();

<div id="progress"> 
  loading 
</div> 
 
<button class="buffer"> 
  reCreateBuffer 
</button>