Many studies suggest that music players used with headphones can emitt sound pressure levels as high as the noises emitted in some industries and working places. Both exposures might be harmful to hearing in prolongate use. Moreover the degree of damage produced by listening to music with headphones is not clearly defined. This has been the motivation for this project which is to investigate the posible presence of a permanent hearing damage due to headphone sound exposure. In order to fullfil this aim, two populations (control and target) which differ significantly in their habits when listening to music from headphones are compared using a headphone sound exposure evaluation an a hearing assessment. This is carried out by testing 20 selected subjects in a listening test. This test consists of a pure tone audiometry, a DPOAE measurement and an analisis of the exposure level of the subjects in different environments. It is concluded that the results obtained could not describe a potential damage by listening to music from a MP with headphones. Moreover, the environment around a person affects the preferred volume setting that this person select in his MP specially when the environment becomes noisy. However, users of MPs with headphones tent to listen to music at higher volume settings than the non users.