Help! I need help with my mic for ps3!!! plz!?

Ok, heres the problem. I was playing Haze for ps3 for the first time with a headset. (online) And my teammates could hear me fine, but whenever they talked to me, i didnt hear them through my headphones on my headset. I could only hear them through my speakers on my TV. So everytime they talked, I could barely hear them. Can someone please tell me how to make my teammates voices come through my headphones on my headset? Thanks a ton!!!