Hi. I have a problem with windows live movie maker 2011 and my computer is windows 7. For a very long time the movie maker have worked very well but lately when I import videos to make movies out of them, I see th visual but no voice ( not for all videos just for some of them). I've thought that maybe it is because of the video when I first observed this problem, but then I've tried a lot more and this problem seems to be increasing. I've read some comments about it, they say it is because of the codecs of video's own and I should delete those codecs. But I don't know how to do that because they were talking about movie maker 2012 and mine was windows live 2011. 

I would be very pleased if there is someone to have a solution to this problem.

( Plus: In the options of movie maker there is no sound section or filters section for codecs I don't know where to find those codecs.)