Katahu: SG-1 DVDs question

Hey Kat, You are the only person I know who has the SG-1 DVDs, so this question is for you. The first season disk3 episode "The Nox" seems to have a problem. You can't hear anything that Apophis is saying. You can hear other sounds related to him (footsteps, weapons fire, ect.) but nothing when he speaks. I know there is probably no way to fix it, but I was wondering if you had the same problem, or if I have a defective disk or something.