If you use an iPod, there is a pretty good chance you are damaging your hearing:

Study Warns of Hearing Loss From Music Players

From the article:

The report said that those who listened for five hours a week at high-volume settings exposed themselves to more noise than permitted in the noisiest factory or work place. Maximum volume on some devices can generate as much noise as an airplane taking off nearby.

The study — from a team of nine specialists on the Scientific Committee on Emerging and Newly Identified Health Risks — also warns that young people do not realize the damage until years later.

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