React v15 Bug

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.3/underscore-min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/2.2.3/jquery.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/backbone.js/1.3.3/backbone-min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.0.1/react-with-addons.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.0.1/react-dom.min.js"></script>

Babel + JSX

var Audio = React.createClass({
  displayName: "Audio",
  
  componentWillMount: function() {
  	console.log("mounting...");
  },
  
  render: function() {
  	return (
    	<audio
        id  = "new_message_sound"
        ref = "messageSound"
      >
        <source
          src  = ""
          type = "audio/ogg"
        />
        <source
          src  = ""
          type = "audio/wav"
        />
      </audio>
    );
  }
});

var Sounds = Backbone.View.extend({
	render: function() {
  	ReactDOM.render(<Audio />, this.el);
    return this;
  }
});

for (var i = 0; i < 1000; i++) {
  (new Sounds).render();
}