My computer doesn't recognize my tv as an audio device


My computer is connected to my tv via HDMI cable. Picture works perfectly but audio doesn't. In playback menu I only see speakers listed but not the TV. However In Nvidia control panel my tv is listed as audio device. Question is, how can I make Windows Vista recognize my TV as audio device.

This is a screenshot of someone's computer I found online. In my playback menu my tv isn't listed although I checked the box that says "show disabled devices".