Only have sound with certain files

[bigpapachiop]

OK, I'm stumped. I have sound if I play songs on Media Player. I don't have sound if I hit someone's My Space page (or my own), so I can't hear the song being played. I have sound if I play video files on the internet, but I don't have sound if I play movie files uploaded from my camera. I don't have sound on flash files or games. What's going on here? Can anyone help?

 

[Tmagic650]

Do you have the latest Flash Player installed? Quicktime may help too. Is your system fully updated using Microsoft's Update website?