Shortly after the iPhone Duo launched, a few users reported hinge issues that were causing cracks in the inner display . Apple has now responded to the reports in a statement to MacRumors , saying a small number of units are affected.

The response to iPhone Duo from early users has been incredibly positive, and we are seeing exciting things from developers who are rapidly updating their apps to take advantage of its unique form factor. We are aware of an issue impacting the inner display on a small number of iPhone Duo units. If users experience issues with their iPhone Duo display, they should contact AppleCare for a replacement.

Apple did not say what causes the cracking, or if a fix is planned. Affected users have been able to get in-store replacements, though with limited stock available, some are having to wait.

According to Apple, the problem is limited in scope.…