why cant i hear ppl talk wen i put on my xbox 360 headet?

[GianlucaC1]

just bought a wired xbox 360 headset and i cant hear people talk. when i play a message i can hear it fine on the tv but then wen i plug the headset it stops and i cant hear anything, i check if it was on muted and adjusting the volume but it still doesnt work and if i buy a wireless one would it work