Apple has in the past charged iPhone 7 users to repair a microphone defect that appeared to many to be a design flaw in the phone. The charge to fix that mic defect was $300, not too far off from the cost of replacing the phone. Apple was offering users a refurbished replacement device for $329 to $349. The microphone in some iPhone 7 devices

Source: Hot Hardware – Apple Slapped With Lawsuit Over iPhone 7 Loop Disease Defect And Substandard Materials