Stricter quality control measures designed to limit the number of scratched iPhone 5 units rolling off the production line have led to a shortfall in supply.
That's according to Bloomberg, which reports that recent complaints of scratches on brand new iPhone 5 units are due to Apple's decision to use a type of aluminium which makes the smartphone thinner and lighter.
Manufacturer Foxconn has been enforcing stricter quality control standards to combat the issue at Apple's request, but this has resulted in slower production and employee unrest, according to numerous sources.
Up to 4,000 employees at Foxconn's Zhengzhou plant were recently reported to have walked off the job in protest, although Foxconn denied a strike occurred.
Fubon Financial Holding analyst Jeff Pu told Bloomberg: "These stricter standards would lower the yield on good products being shipped out. They'll handle it by increasing labor and machinery, and Apple may even use its cash to buy new equipment to assist Foxconn."
iPhone 5 sales hit five million units in the device's first week of availability, according to Apple.