San Francisco: In a “very small number” of 2018 MacBook Air units, Apple has identified a logic board issue and is offering a free replacement of the component to the owners of the affected computers. The iPhone-maker circulated the information via an internal document that was distributed to Apple Stores as well as Apple Authorised Service Providers, Digital Trends said in a report on Sunday. According to documents obtained by media publications, they refer to the main logic board in the Retina, 13-inch, 2018 MacBook Air with certain serial numbers. To inform the affected users for their free logic board replacement, Apple would contact them through an email, the report said. (IANS)