Re: Muffled/quiet AirPods when on call
You may want to check you are not on mute, and the audio is directed to the AirPods during a call.
see Apple support's online article: While on a call on iPhone - Apple Support
Eg: says
"Adjust the audio during a call
To
change the volume, press the volume buttons on the side of iPhone. Or
swipe down on the call banner, then do any of the following:
- Mute: Tap the mute button.
- Put the call on hold: Touch and hold the mute button.
- Talk handsfree: Tap the audio button, then choose an audio destination."
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Else: Have you checked the iPhone microphone itself is working ok ... (eg in a Voice Recording_
You may need to remove any screen protectors, films or cases from your iPhone.
You can check for any spot of dirt or wax, or clear any debris, from the openings of your iPhone.
see: Cleaning your iPhone - Apple Support