Wrong URL in [audio] WordPress shortcode

I have a problem with WordPress Audio Shortcode. I used it like this:

<?php 
echo do_shortcode('[audio mp3="http://ift.tt/1A3N4e2" ogg="http://ift.tt/1MiYzVy"]');
?>

but in front, in HTML code I got:

<!--[if lt IE 9]><script>document.createElement('audio');</script><![endif]-->
<audio class="wp-audio-shortcode" id="audio-362-1" preload="none" style="width: 100%; visibility: hidden;" controls="controls">
    <source type="audio/mpeg" src="http://ift.tt/1A3N4e4" />
    <source type="audio/ogg" src="http://ift.tt/1MiYykh" />
    <a href="http://ift.tt/1A3N4e2">
        http://ift.tt/1A3N4e2
    </a>
 </audio>

like you can see, in <source/> tag URL to audio file is incorrect (in <a/> tag, URL is OK). It has some strange "?_=1" at the end of URL, and of course, player does not work. Browser does not recognize multimedia file.

Can you help me? Do you know how can I fix it?

regards