crackling sound in one of my AirPods

Hi beachgirl1701,

We appreciate you reaching out to us. We understand that you are reaching out because you can hear a crackling sound on one of your AirPods.

We’d like to gather additional details that may help us be in a better position to assist you.

1. Are you experiencing the issue on multiple apps?
2. Are you able to replicate the issue with a different AirPods supported device?

If you are currently using your AirPods with an iPhone or iPad, please check for a software update and make sure that you are running the latest version of iOS or iPadOS.

While it isn't inherently assured that an update will resolve the issue, updating to the latest software version for your device can help isolate potential software issues. 

Kindly secure a backup and update.

1. How to back up your iPhone, iPad, and iPod touch
2. Update your iPhone, iPad, or iPod touch

Next, please make sure that the affected AirPod is free of any dirt or debris.

Also, please check if your AirPods are running on the latest firmware.

About firmware updates for AirPods - Apple Support

If your devices are up to date, please reset your AirPods.

You can use the steps below as a guide.

1. "Put your AirPods in their charging case, and close the lid.
2. Wait 30 seconds.
3. Open the lid of your charging case, and put your AirPods in your ears.
4. Go to Settings > Bluetooth. Or go to Settings > [your AirPods]. If your AirPods appear there as connected, tap the More Info button  next to your AirPods, tap Forget This Device, then tap again to confirm. 
5. Put your AirPods in their charging case, and keep the lid open. 
6. Press and hold the setup button on the back of the case for about 15 seconds, until the status light on the front of the case flashes amber, then white.*
7. Reconnect your AirPods: With your AirPods in their charging case and the lid open, place your AirPods close to your iPhone or iPad. Follow the steps on your device's screen."

You can use the article below as a reference.

How to reset your AirPods and AirPods Pro - Apple Support

Take care!