[cameldrv]

I've had this happen three times now in 2.5 years. The first symptom is that the noise cancellation gets worse. Some months after that, you start hearing a crackling sound, particularly while speaking, or if you adjust the airpod in your ear.

I believe what is happening is that earwax is building up in the grille on the top inside of the airpod which houses a microphone. As the sound from this microphone gets more distorted, the noise cancellation gradually stops working. You can also see this because after you've had the airpods a couple of months you will never get the ear tip fit test to pass.

Every time this has gotten to the crackling stage, Apple has replaced these without charge, even though I didn't have Applecare. They have some sort of machine in the back of the store that they use to test them, and if your set fails the test, they give you a new pair (sometimes just one).

[gnicholas]

Wow, thanks for sharing this. I've had mine for 9 months and just started hearing the crackling noise. I didn't know this was a widespread issue or that Apple addresses it so easily. Fingers crossed...