ac3 filter background sound but no actors voices

[evilscrappy]

I am running windows vista ultimate 64 bit,using vlc 1.1.7(tried 1.1.same thing
I believe its the ac3 filter,I can play the movie have video,background sound but no acors voices.
Any ideas?
I noticed when I updated to 1.8
now a movie that I used to play with no problem before updating worked fine,now after update and then going back to 1.1.7 same movie has these issues.