Samsung Galaxy S20 family speaker is quiet, distorted or has no sound

A Galaxy S20 whose speaker is silent, crackling or muffled has a list of causes that Asurion's guide and owner threads put in a consistent order. Check the simple settings first: the volume sliders in Settings, Sounds and vibration, Volume; Do Not Disturb, which silences alerts; and Bluetooth, since a phone connected to a headset or car sends sound there. Restart the phone. Then look at the speaker grille at the bottom edge for lint and dirt, and clean it with a soft brush. The S20 is water resistant, but water in the speaker causes a robotic, muffled sound until it dries;

the guidance is to dry the phone, avoid using the speaker at high volume until the sound clears, and wait. If the sound is silent only on calls, the earpiece grille at the top may be blocked. Software updates and a cache wipe can fix a speaker that stopped after an update. A useful check is to play sound through a wired headset or a Bluetooth speaker: if audio plays there, the phone's audio system works and the fault is limited to the speaker or its grille; if no sound plays anywhere, a software fault is likelier. Also test the earpiece in a call, since the S20's loudspeaker and earpiece are separate parts.