I downloaded a flv video to my computer but there is n sound?

I have a mac computer and I recently downloaded a flv video to my computer but when i play it there is no sound. I downloaded wmv videos and have a plug in to play them, but no problems there. flv files use to work fine until i downloaded the wmv files. how can i get the sound back? You may download VLC player for a try, it's a powerful video player that supports both flv and wmv video, go and google search for it.Or you can convert flv video to mov video, then you can play it with quicktime player. I know flv video converter Mac supports mov video better than flv video. If you don't know how to convert video, here is a guide for you