title: ios AVAudioPlayer get wrong duration
body: <p>I use <a href="https://github.com/nickcheng/NCMusicEngine" rel="nofollow">NCMusicEngine</a> to achieve playing mp3 while downloading But when I play some specific remote mp3 file I get the duration of mp3 is wrong, example I get the value is 58 it shoule be 29 It looks like double of the actual value , then I play the remote mp3 in chrome ,it works fine,  </p>
  
  <p>I try to use <code>AVAssetURL</code> to get the duration of remote mp3 file ,the same error is happen</p>
  
  <p><strong>what happen?</strong></p>