If you have to use a HDMI to DVI converter to your TV, that means that you have no HDMI input in your TV. HDMI carries audio; DVI connections do not. Even though you can use the converter for video, that doesn't magically create the ability for your TV's DVI input to accept audio.
You need to use a different connection for audio, and I'm going to assume that your TV just has analog (r/l inputs, white/red), which you'd have to use, unless my assumption's wrong and you have an optical audio input on your TV.
Let us know what make/model your TV is, and I'm sure we could find out what audio options you have.
Edit: Dang, I got beat!
Two things are infinite: the universe and human stupidity. And I'm not sure about the universe. -- Albert Einstein