BEIJING, Dec. 25 (Xinhuanet) -- Apple is developing an automatic volume control device for iPods amid growing fears that its users are at risk of hearing damage from listening to loud music, according to London-based Daily Mail on Monday.

    The next iPods and iPhones could automatically calculate how long a person has been listening and at what volume, before gradually reducing the sound level, a new patent said.     

    "Since the damaging effect on users' hearing is both gradual and cumulative, even those users who are concerned about hearing loss may not behave in a manner that would limit or minimize such damaging effects," the patent stated.

    The device will also calculate the amount of "quiet time" between when the iPod is turned off and when it is restarted, allowing the volume to be increased again to a safe level.

    Listening to volumes below 70 decibels is considered safe. However, iPods currently can reach volumes of over 100 decibels, enough to cause permanent damage after just 15 minutes.

    Some MP3 players can even exceed 120 decibels.

    The UK's Royal National Institute for Deaf People (RNID) claimed that more than four million young people aged between 16- and 24-years-old are at risk of hearing damage from listening to loud music.

    Its research showed more than half of that age group were listening to digital music players for more than an hour a day. Twenty percent notch up more than 21 hours a week.

    "If young people don't heed our warnings about safer listening, they could end up facing premature hearing damage," RNID chief executive Dr John Low said.

    Low said it could help to protect the hearing of millions of its customers, if the next generation iPods do what the patent claimed.

    (Agencies)