Apple iPhone X Has a Romeo and Juliet Problem

Apple’s iPhone X might have a big manufacturing problem. And its facial-recognition feature could be the blame.

The tech giant’s manufacturing partners are having trouble quickly assembling so-called Romeo and Juliet modules for the iPhone X’s Face ID facial-scanning feature, causing fears of a supply shortfall when the smartphone is released in November, The Wall Street Journal is reporting, citing people who claim to have knowledge of Apple’s problems.

According to the Journal, Romeo and Juliet are two separate components that are integral to Face ID’s functionality. The Romeo module beams a laser at a person’s face to identify facial features, contours, and more. The Juliet module takes that information and interprets it to ensure the person trying to activate the iPhone X is verified to do so. Without either component, the iPhone X’s central security feature will not work.

The Journal‘s sources say Apple’s (AAPL) manufacturing partners have had trouble assembling all of the components in Romeo, leaving too few completed parts to match up with the Juliet module.

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Rumors have been floating for weeks, suggesting Apple is facing some trouble with its iPhone X production. Some reports have said that Face ID has been the bottleneck, and others have said Apple is having trouble getting enough screens for its upcoming smartphone.

Apple has remained silent about its possible manufacturing woes, but the company’s decision to release the iPhone X in November instead of a September timeframe like its iPhone 8 might be telling. Apple, it seems, needed some additional time to get its high-end smartphone to store shelves.

But exactly how this Romeo and Juliet problem will affect the iPhone X is unknown. The Journal‘s sources said that the problems have largely been addressed, and now the production process is moving along at a reasonable pace. But considering Apple has faced both screen and Face ID manufacturing problems, there’s a chance that its supply will be constrained for at least some time.

Apple’s iPhone X goes on sale on November 3. Apple will begin taking pre-orders on the handset on October 27. The iPhone X starts at $999.

Apple did not immediately respond to a Fortune request for comment on the Journal‘s report.

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