Apple is reportedly notifying affected customers by email.

We’ve asked Apple for comment. The low-key nature suggests this isn’t a widespread problem, but the timing is less than ideal. It comes days after Apple recalled some older MacBook Pros over battery issues, and weeks after the company made MacBook keyboard repairs a higher priority. Still, it’s good to know that Apple is tackling these issues directly instead of leaving customers to wonder (and in some cases pay out of pocket).