The invention provides a hearing protection device (10, 20) having an attenuating body (12, 22) composed of an elastomer with an increased glass transition temperature and a reduced glass-to-rubber transition temperature such that the damping factor of the material peaks at a higher temperature and, resultantly, the damping factor is increased over a range of temperatures and frequencies typically experienced by the device during usage. The increased damping results in higher sound attenuation provided by the hearing protection device (10, 20).