The iPhone maker over the weekend launched an official service program to replace AirPods that have begun making a crackling or static sound. On its page, Apple explains that it “has determined that a small percentage of AirPods Pro may experience sound issues,” noting that crackling may increase in loud environments.

Other users may experience problems with the headphones’ active noise cancellation feature, which could eliminate bass in music or actually amplify background noises.

Users running into the hardware glitches will be eligible to receive free replacements of the faulty earbuds. A replacement AirPod would normally cost $89 for each bud, not including its wireless charging case.

Apple isn’t guaranteeing the AirPods against any hardware failure, however. The offer will only be eligible for two years after the purchase of the defective unit.

Apple recently eliminated the free wired headphones it normally includes in the box with each iPhone, as AirPods have become a multi-billion business on their own.

It’s not the first time Apple has had to offer free replacements for faulty products. Back in 2018, the company introduced a repair program for the “butterfly” butterfly, which Apple had introduced to enable ever-thinner laptops, but which proved faulty.