With millions of iPods and other MP3 players in the hands of consumers, the portable media players have made a racket in the marketplace for years. Now some experts warn that the devices make too much noise. A new study from the European Union cautions that people who listen to personal music players for too long, at too high a volume setting, may do serious damage to their hearing. The report estimates that up to 10 percent of users could start losing their hearing within five years, and most don’t realize it.
