Apple Watch Ultra 2 speaker or microphone is muffled

The checks in more detail

Test the microphone with Voice Memos on the watch. If your voice is faint on calls, hold the watch closer to your mouth, since the microphones are on the case edge. The siren is separate and loud on purpose; if it plays by accident, check the Action button's setting. A watch that is silent or crackling after the steps needs Apple. The Ultra 2 has a Depth app and a Compass Waypoints feature that use sensors rather than the speaker, so they will not help with sound faults, but the Siren's long press on the Action button is a quick test of the speaker's loudness and shows that the hardware is working.

Use it for a second only, since it is very loud and attracts attention, and stop it by pressing the button again or via the on-screen control. The Ultra 2's three-microphone array is designed to reduce wind noise on calls, and in heavy wind the watch applies strong filtering that can make your voice thin. If you are making a call outdoors, turn your back to the wind or cup the watch. For dictation, speak in short phrases. The Ultra's large speaker is also used for Siri responses and the Depth app's alerts under water.

After a dive, rinse the watch in fresh water and run the Water Lock eject twice, drying the case between runs. The Ultra 2's Action button can be assigned to the siren or to a workout, and a long press triggers the siren, so a button that is pressed in a bag or under a sleeve can sound the siren by accident. If that is happening, change the Action button's function or turn off the siren's long-press setting in Settings, Action Button, and check the button for debris that holds it down.