title: How to play .m4a with HTML5 audio in IE(9+) and Safari (Pad)?
body: <p>I need to play .m4a files (recorded on iPhone) in IE(9+) and Safari (iPad, iPhone). I am facing problem with setting correct MIME Type. For playing in IE10 I need to set  <code>audio/mp4</code> but for Safari <code>audio/aac</code>. <br>
  With <code>audio/mp4</code> I am getting  <code>Cannot play audio file</code> on iPad.
  With <code>audio/aac</code> I am getting <code>Error: Unsupported audio type or invalid file path</code> in IE</p>
  
  <p><strong>Is there a type I can set for both?</strong></p>
  
  <pre><code>&lt;audio controls="controls" autoplay="autoplay"&gt;
     &lt;source src="play.aspx?filename=sound.m4a" type="audio/mp4" /&gt;
  &lt;/audio&gt;
  </code></pre>
  
  <p>Notes</p>
  
  <p>Using an alternative player is not a solution for me.</p>
  
  <p>I serve the files thorough .aspx page so I can control HTTP headers. </p>
  
  <p>From observing the page <a href="http://www.coolestguyplanettech.com/html-5-audio/" rel="nofollow noreferrer">HTML 5 Audio Across All Browsers using m4a, oga, mp3 and Flash</a> it seems that possible solution is to give <code>type="audio/mp4"</code> and NO conten-type header. However removing HTTP header in aspx is rather too complex for problem I am trying to solve(see <a href="https://stackoverflow.com/questions/12803972/removing-hiding-disabling-excessive-http-response-headers-in-azure-iis7-without">Removing/Hiding/Disabling excessive HTTP response headers in Azure/IIS7 without UrlScan</a>).</p>