Strange Audio Problem

Ok hey everyone I am new here and I have been struggling with this problem and it is stressing me out. I have read the avi codecs guide and everything.

My problem is that when I try to play some of the avi files I have what happens is I can see the video perfectly fine and I can hear the music and what not in the background of the beginning, but once the movie starts the characters lips move but there is no audio whatsoever. I have used AVIcodec to make sure I have all the proper codecs installed, and it says they are supported. Has anyone else ever had this problem before. Its frustrating because the video and background sounds work but there is no voice audio.

More specifically these are the files that it is happening with.
Natural.Born.Killers.1994.DC.iNTERNAL.DVDRip.XviD-XviK
Frost.Nixon.LiMiTED.DVDSCR.XviD-DoNE

Any help would be greatly appreciated as I have tried everything I know of and am now forced to ask for help

Thanks,
Funk

 

Also I have tried playing these files in VLC media player and Windows media Player and neither one works.

 

You have to narrow it down.
For example, do the problem files have ac3 audio, or mp3?
Or both?

 

the problem is with the AC3 audio and I have already installed AC3Filler so that doesnt work

 

Open up ac3filter. See if there is a section that deals with your
speaker setup. See if it agrees with your physical speaker setup.