Vista - problem playing audio on websites

Hi the website we are talking baout is www.cause4concerndnb.com and in the audio section the m3u's are not asking media player to open up and play on some vista machines using ie 8 and media player 11 the page they get instead of the stream is the files do exist on the server and do play on xp machines and in firefox please can someone say why this could be happening please, but also i may add it doesnt not work on some machines i have tested on so could it be media player Vist or IE or antivirus firewall etc.. ,really need to have some answers on this Thanks look forward to a reply .

ok all is cool now ive worked it out =

to do with IE and frames as im hosting the site on my another server and
cos the c4c-site is just a frame IE prolly gets confused or thinks its a XSS attack
XSS = cross site scripting = security flaw all done used mp3 files instead of m3u's pointing to mp3's