New hardware always seems to have its share of problems, and Apple has confirmed to The New York Times that this time around some iPhone 5S owners are experiencing poor battery performance. "We recently discovered a manufacturing issue affecting a very limited number of iPhone 5S devices that could cause the battery to take longer to charge or result in reduced battery life," Apple spokesperson Teresa Brewer told the Times in a statement. "We are reaching out to customers with affected phones and will provide them with a replacement phone." The Times points out that a defective battery is not the same thing as a "manufacturing issue," indicating that bad components aren't necessarily to blame.

Apple declined to state how many phones were impacted, but interest in the iPhone 5S has certainly been intense: between it and the new 5C, Apple sold more than 9 million new iPhones in their first weekend of release. We've reached out to Apple for further comment.