title: Can't set currentTime for audio in javascript (only IOS)
body: <p>I want to create a script that allow user start play audio from 20nd seconds, it work well on all browser and device, except on IOS.
  Here is the code</p>
  
  <pre><code>document.addEventListener('DOMContentLoaded',function(){
      var audio = new Audio();
  
      document.getElementById('play').addEventListener('click',function(){
          audio.src = "test.mp3";
          audio.play();
          audio.pause();
          audio.currentTime = 20;
          audio.play();
          alert(audio.currentTime);
      });
  });
  </code></pre>
  
  <p>When debugged, on IOS browser, such as chrome on iphone, the alert value was 0 second, other cases return 20. The audio was played normally.
  Which points am I wrong? Thanks for help!  </p>