Well, is not exactly the x300t that is filtering vuvuzelas, but Portugal Telecom's Meo iptv service(mediaroom based) came up with a clever aproach for filtering the vuvuzelas: http://translate.google.com/translate?js=y&prev=_t&hl=en&ie=UTF-8&layout=1&eotf=1&u=http%3A%2F%2Farrifana.org%2Fblog%2F2010%2F06%2Fvuvuzelas-servico-publico%2F&sl=pt&tl=en