I have this same headset (Mikomi HS-819) and use it for PS3. I've set it up correctly and i'm pretty sure of this but when I play Call of Duty 4: Modern Warfare the little speaker symbol is there and I can hear my mates fine on the headset and very loudly but the mic doesn't seem to pick up any sound. It's really annoying me and I bought it off my mate and he says its fairly new and hes used it 3 or 4 times on his PS3 and it worked fine for him.

Does anyone know how to sort this on PS3?