The S21+ has the same stereo speaker design as the rest of the S21 series, with the earpiece as the top speaker, and the Samsung Community threads on S21 sound problems describe a muffled or crackling top speaker. Run the speaker test in Samsung Members, Phone diagnostics, first: it plays a tone through each speaker and tells you which one is weak. Check the Sound settings for Dolby Atmos and Equaliser, turn them off for a test, and check volume limits. A case or protector that covers the earpiece slot muffles sound.
The checks in more detail
Dust in the grille builds up over the years, and a soft brush helps. Owners report that removing and reinserting the SIM tray cures crackling after pressure changes. The *#0*# hardware menu has speaker and receiver tests. Update the software and test in Safe mode. If one speaker is silent in the diagnostic, a repair is needed. Water resistance means the phone keeps moisture in the speaker cavity after a splash, so let it dry. The S21+ is old, so a replacement speaker is a common repair.
The S21+ speaker's loudness can also be limited by Samsung's Hearing protection or by Sound balance settings in Accessibility, so check them if only one side seems quiet. Playing a stereo test file shows left and right separately, and an adjustment to the balance slider fixes it if the settings are the cause. If the speaker works in speakerphone calls and not in media, check the app's own sound settings, since some video apps have a mono or night mode that changes balance.
Compare with a music app and with a ringtone to find which path fails. Record your findings so that a repair desk can see the pattern. To rule out a software cause, boot into Safe mode and play the same file, and compare with the Samsung Members speaker test. If both are clean in Safe mode, an app or a sound effect is responsible and removing recent audio apps, equaliser tools or boosters resolves it. Many volume booster apps produce exactly the crackle owners describe, so uninstall them.
Differential
Likely causes of “Samsung Galaxy S21+ speaker is quiet, distorted or has no sound”, and how to tell them apart
- 1
A weak top speaker
What separates it Sound is lopsided
How to confirm Run the speaker test to confirm
- 2
Dolby Atmos or Equaliser
What separates it Distortion in some sounds
How to confirm Turn them off to test
- 3
A case or dust over the grille
What separates it Muffled sound
How to confirm Remove the case and brush the grille
- 4
Trapped pressure or moisture
What separates it Crackle after flights or water
How to confirm Eject and refit the SIM tray; let it dry
- 5
A failed speaker
What separates it The diagnostic fails
How to confirm Samsung service
Before you touch a setting
Record this first — changing settings destroys the evidence
- Which speaker is weak
- Whether effects are on
- Whether the phone got wet or flew
- The diagnostic result
Try in this order
0 of 8 completedRun the speaker test
ReversibleIn Samsung Members.
Turn off Dolby Atmos and the Equaliser
ReversibleIn Sound quality and effects.
Remove the case
ReversibleAnd brush the grille.
Refit the SIM tray
ReversibleTo release pressure.
Test in Safe mode
ReversibleTo rule out apps.
Contact Samsung
ReversibleIf a speaker is silent.
Check Sound balance
ReversibleSettings, Accessibility, Hearing enhancements.
Play a stereo test file
ReversibleTo check each side.
Model-specific
What is true of this model and not of its siblings
- Diagnostics
- The Samsung Members test identifies the weak speaker.
- Moisture
- Water resistance traps moisture.
- Balance setting
- A moved slider silences one side.
- Test files
- They show left and right.
Stop boundary
When this stops being a self-service repair
- !If one speaker is silent in the diagnostic, book a repair
- !If crackle returns after the pressure trick, contact Samsung
- !Water damage needs service
Evidence ledger
Sources behind this answer
S21-series owners describing crackling and the fixes tried.
The top speaker crackling on an S21-series phone.
Samsung's own steps for a speaker with no or poor sound.
Exact questions
Common questions
Why is my S21+ top speaker quiet?+
A blocked grille or a weak speaker.
What does the speaker test do?+
It plays a tone through each speaker.
Will drying help?+
After a splash, yes.
Can I replace the speaker?+
Samsung can.
Why is one side quiet?+
Balance or a weak speaker.
Where is Sound balance?+
In Accessibility.