iTunes Festival Stream Picture freezes

Hey guys,

i wanted to watch the deadmau5 stream yesterday but every time about 15 secs after i started the stream the picture freezes for about 3-5 secs while the sound worked fine. I thought it may be because of the Apple Server being busy, and so i wanted to watch it now. But still i have the same problem. Picture freezes while sound countinues.. I use the lates version of iTunes (64bit) for Windows 7 (64bit). Normally i have no problems with streaming, so i don´t think that my internet connection may be the problem. As far as i remember i already had the same Problems last year.. Any suggestions?