Samsung Galaxy S24+ microphone is quiet, muffled or not working

The checks in more detail

Check for Bluetooth, as a watch, earbuds or a car may be taking your voice, and unplug any USB-C headset. In Settings, Privacy, Permission manager, Microphone, make sure the app you use is allowed, and in the Quick panel check that the microphone access toggle is on. Samsung has call settings that change the voice: in the Phone app, open Settings, then look for Noise reduction and Voice Clarity options, and test with them on and off, since a feature meant to remove background noise can clip a quiet voice.

Samsung Voice Focus, found in some call and video apps, can also affect how it sounds. Look at the physical side: a case or a thick screen protector can cover the top microphone, and lint at the bottom hole muffles sound, so clean gently with a dry brush. Restart the phone and test in Safe mode to see whether an app interferes. Check for a software update, as Samsung patches fix call-audio bugs. If the video test is quiet in Safe mode, the microphone hardware is faulty, and Samsung or a repair shop should replace it.

Back up before sending the phone away, and note that the S24+ has water resistance that service must reseal. If your voice is fine on normal calls but poor in a particular app such as a video call, check that the app is not using a different input, for example the earbuds' microphone, and look at the app's own audio settings for a noise filter. Also test with the phone's own Voice Recorder in its three modes, Standard, Interview and Speech-to-text, which use the microphones differently and show whether one is weaker than the others.