: Swipe down from the top-right corner to open the Control Center and use the vertical volume slider.

when voices sound too loud, you must use the physical side buttons . Adjusting the volume from the Home screen often only changes the ringer or media volume, not the in-call speaker. Immediate Solutions During a Call

: You can ask Siri to "Turn down the volume" during a call. Additional Settings to Check

To lower or adjust the call volume on your Go to product viewer dialog for this item.

If the volume remains too loud even at the lowest setting, check these accessibility and safety features: Adjust the volume on iPhone - Apple Support

: Press the Volume Down button on the left side of the device while the call is active to lower the earpiece or speaker volume.