One of my AirPods sounds very muffled. They are new and I have tried everything to get it to work. Any suggestions?

Hi una148, welcome to the Apple community

I hope you are doing well 🤗

I invite you to try this :

1/ Put your AirPods in their charging case, and close the lid.

2/ Wait 30 seconds.

3/ Open the lid of your charging case.

4/ With your AirPods in your ears and connected to your iPhone, iPad, or iPod touch, go to Settings > Bluetooth, or Settings > [your AirPods], and tap the More Info button next to your AirPods. If you don't see your AirPods in Settings > Bluetooth or in Settings > [your AirPods], just go to the next step.

5/ Tap Forget This Device, and tap again to confirm.

6/ With the lid open, 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, iPad, or iPod touch. Follow the steps on your device's screen.

-If your AirPods won't connect - Apple Support

-If your left or right AirPod isn't working - Apple Support

-How to clean your AirPods, AirPods Pro, AirPods Max, and EarPods - Apple Support

-How to reset your AirPods and AirPods Pro - Apple Support

Any suggestions to stop the muffled sound on my new AirPods?

If your AirPods are new I invite you to exchange them or organize a repair. Contact Apple support.

Apple support is available here: Apple Support

See you soon👋

Julio