Apple Computer faces a lawsuit that alleges the company knew its nano portable music player was defective but still decided to press on with the product's release last month.
The lawsuit depends on a US judge to decide whether it can be grouped with other complaints to win class action status. Sales of iPods account for almost a third of sales.
The credit card-sized nano, which replaced the bestselling iPod mini and is smaller than the traditional iPod, met with rave reviews.
But users quickly started grumbling on internet message boards that the device's screen scratches too easily.
The lawsuit, filed in San Jose, California, claims that the nano scratches " excessively during normal usage".
It alleges that though Apple knew the nano had design problems, it released the product and led consumers to believe it was durable.
The complaint blames the nano's defectiveness on the film of plastic resin that covers it to protect it from damage. Previous versions of the iPod were coated with thicker and stronger resin, the suit says.
"Rather than admit the design flaw when consumers began to express widespread complaints Apple concealed the defect and advised class members that they would need to purchase additional equipment to prevent the screen from scratching excessively," the complaint says.
Apple, which opened its second UK store at Birmingham's Bullring, has admitted that some iPod nano screens cracked too easily, but blamed that separate issue on vendor quality problems and said it had occurred in less than onetenth of one per cent of the nanos sold at that point.
Apple's iPod has a share of 75 per cent of the US market for MP3 players.
The plaintiff named in the California lawsuit, Jason Tomczak, bought a nano in September. He said it quickly became so scratched he could not view the screen.
Apple replaced that device because of a battery problem, but the complaint claims the replacement nano also became so scratched that Tomczak decided to return it.
Because Tomczak and other complainants were required to pay a $25 fee to return the nano, the proposed class action suit seeks the return of those fees along with the device's original cost and several other forms of damages.
An Apple spokesman could not be reached for comment.