A federal appeals court on Wednesday rejected a class-action lawsuit seeking to hold Apple Inc responsible for possible hearing loss caused by using its popular iPod music player.

The Ninth Circuit Court of Appeals in San Francisco affirmed a 2008 district court ruling that the plaintiffs failed to show that use of the iPod poses an unreasonable risk of noise-induced hearing loss.

It also found that the plaintiffs lacked standing to allege a violation of California's unfair competition law.

Jeff Friedman, a Berkeley, California lawyer representing the plaintiffs, did not immediately return a call for comment. David Bernick, who represented Apple, had no immediate comment. An Apple spokesman was not immediately available for comment.

Cupertino, California-based Apple has sold more than 220 million iPods since their 2001 launch. It provides a warning with each iPod that urges users to avoid hearing damage by setting the volume at safe levels.

The plaintiffs, Joseph Birdsong and Bruce Waggoner, had argued that the iPod ear buds are designed to be placed deep in the ear canal, which increases the danger of hearing damage.

They also said that iPods pose a danger because of their lack of volume meters or noise-isolating properties, despite being capable of producing sound as loud as 115 decibels.

The appeals court said the plaintiffs showed ways they believe iPods could be made safer, not that they were dangerous.

The plaintiffs do not allege the iPods failed to do anything they were designed to do nor do they allege that they, or any others, have suffered or are substantially certain to suffer inevitable hearing loss or other injury from iPod use, Senior Judge David Thompson wrote.

At most, the plaintiffs plead a potential risk of hearing loss not to themselves, but to other unidentified iPod users, he wrote.

The plaintiffs had sought money damages, and to require Apple to improve safety and disclosures, provide better headphones, and test iPod users for hearing loss.

Apple shares rose $1.43 to $210.53 in afternoon trading on the Nasdaq.

The case is Birdsong et al. v. Apple Inc. U.S. Court of Appeals for the Ninth Circuit, No. 08-18841.

(Reporting by Jonathan Stempel. Editing by Robert MacMillan)