Apple has posted a software update for the iPod nano and fifth generation iPod that makes it possible for owners of those iPods to set a limit on the volume levels.

The company suggests the software update 1.1.1 can be used by parents who wish to "set a maximum volume limit on their child’s iPod and lock it with a combination code". It is likely that the move is in response to recent concerns about the link between listening to devices such as iPods, and hearing loss.

The iPod maker was recently sued by a man in Louisiana who claimed he had suffered hearing loss.

Apple vice president of Worldwide iPod Product Marketing Greg Joswiak said: "With the increased attention in this area, we want to offer customers an easy-to-use option to set their own personal volume limit."

The Volume Limit feature works with any headphone or accessory plugged into the iPod headphone jack as well as the iPod Radio Remote. The free download is available from Apple's website .