Help with my laptop output to tv.?

I connect my hp laptop to my tv using an hdmi cable. The video works fine, but after trying everything in the control panel>sound category, nothing works. But here's the wierd thing. WHen i set it to digital output(hdmi) the only sund that actually comes out of my tv is when i press the quickplay buttons, and it makes that little boop sound. Please help 10 points.