Just a random guess/idea. Is this on every movie you watch or just specific ones? I find that some of my DVDs were poorly mixed. Especially those that are dubbed in some form (Anime). So the speaking parts are far too low, but when the action comes I have to turn it down. For example Vampire Hunter D: Bloodlust is so poorly mixed that I have only watched it through once even though I enjoy the film. But I get sick and tired of adjusting the volume up and down.

jr

"What can be asserted without evidence can also be dismissed without evidence." C Hitchens