Combo Jack Audio Adapter not working

I recently bought a StarTech Headset adapter for my dell alienware 15 laptop to make it so I could use my headphones in my combo jack. I plug my headphones into the adapter, then into the laptop and I hear static. That is the only noise they play though. Sound still comes out the laptop's speakers and when I try to change playback devices there is nothing but the speakers in the laptop. Any help getting this to work would be appreciated.