There are no definitive answers from Arcsoft, the creators of the Total Media software, on why this happens. Here are some possible solutions –

1.       Install the free AC3 Filter decoder that is available at this link - http://ac3filter.net/projects/ac3filter/releases

2.       Install the Windows Media and Audio codec available at this link – http://kaiserbaas.helpserve.com/Knowledgebase/Article/View/169/33/windows-media-codecs

3.       Install the latest version of Direct X 9.0 available at this link - http://www.microsoft.com/downloads/en/details.aspx?FamilyID=2da43d38-db71-4c1b-bc6a-9b6652cd92a3&displaylang=en

*Please note; Direct X 11.0 is already included with Vista Service Pack 2 and Windows 7 therefore this update is not required.