Check battery: place each earbud in the case, wait 30 sec, then check status on iPhone.
Clean speaker mesh and charging contacts using a soft brush or dry cotton swab.
Reset AirPods: forget device and hold case button 15–30 sec until light flashes white.
Adjust audio balance: Settings > Accessibility > Audio/Visual > center Balance slider.
Update iOS and leave AirPods in case to receive firmware updates automatically.
If still faulty, hardware issue likely – replacement earbud costs around $69 USD per side.
Support resources available via Apple Support and repair guides on Web/YouTube.