Review of fix for audio bug

Manage URL - http://rdn-test.appspot.com/#PRESENTATION_MANAGE/id=2730eea1-4caf-4ddd-becb-73279d336b9c/company=b428b4e8-c8b9-41d5-8a10-b4193c789443
Preview URL - http://viewer-test.appspot.com/Viewer.html?type=presentation&id=2730eea1-4caf-4ddd-becb-73279d336b9c&showui=false

@donnapep @ByronDarlison 
Review of fix for Bug #11