SAN JOSE, Calif. — Apparently, Apple Computer Inc. is listening.

In a world where hearing problems are real, concerns are mounting and lawyers are looking to make gadget providers liable, the maker of the predominant iPod music player has created new volume controls.

Apple issued a software update yesterday for its recent iPod models — the Nano and the video-capable iPod — allowing users to set how loud their digital music players can go.

Parents also can use the feature to impose a maximum volume on their child's iPod and lock it with a code.

Sandy Liao, a Fremont mother of two, welcomed the development, although she wants to see Apple add the feature to the models she has, the Shuffle.

She had avoided buying her children any kind of portable music player out of concern they would damage their ears, but a friend gave a Shuffle to each of her children, ages 9 and 10, as gifts last year.

"It would be great if I could get the volume controls for them, too," she said.

Apple representatives said little about why they made the change, issuing only a statement.

"As the leading provider of digital music players, Apple continuously brings iPod customers innovative and easy-to-use solutions," said Greg Joswiak, Apple's vice president for iPod marketing. "With the increased attention in this area, we want to offer customers an easy-to-use option to set their own personal volume limit."

Whether Apple is responding to legal challenges or specific consumer requests, industry analyst Michael Gartenberg of JupiterResearch said the issue clearly is a concern, and "Apple is acting in a responsible way to address it."

Earlier this year, a Louisiana man sued Apple, claiming that the iPod can cause hearing loss.

The devices can produce sounds of more than 115 decibels, a volume that can damage the hearing of a person exposed to the sound for more than 28 seconds per day, according to the complaint filed in U.S. District Court in San Jose, Calif.

Although the iPod is more popular than other types of portable music players, its ability to cause hearing loss isn't any higher, experts said.

Apple has sold more than 42 million iPods since the original model debuted in October 2001.