Apple is promising free repairs for faulty MacBook keyboards after waves of complaints about malfunctions.

The company said it has "determined that a small percentage" of MacBook and MacBook Pro keyboards may have misfiring keys that unexpectedly repeat or do not produce characters or have keys that feel "sticky."

The company's own technicians or authorized service providers can provide the remedy. It may include replacing one or more keys or the entire keyboard, Apple says.

Laptops eligible for free service include certain 12" to 15" laptops made between early 2015 and 2017. A full list of models can be found here.

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Apple says customers who have one of the affected laptops and already paid for a repair can contact the company for a refund.

Reports of issues with Apple's butterfly-style keyboards, first introduced on the MacBook in 2015, have been common online.

Apple said the butterfly design was 40% slimmer than older versions and would provide more precision. But tech site The Verge has called the keyboards "famously problematic." A piece from the online publication The Outline also declared: "the new MacBook keyboard is ruining my life."

At least three lawsuits have been filed against Apple that center on the butterfly keyboards, according to a tally by 9to5Mac.com, an Apple-centric blog.