There are two ways people arrive at this page. Either the sound went bad suddenly, in which case something happened and you probably know what it was, or it got worse so slowly that you only noticed when someone else’s phone sounded better than yours. The second is far more common and far more fixable, because nothing is broken — the speaker has just been slowly buried.
Work down this list in order. It is arranged by how likely each cause is and how cheap it is to rule out.
1. Water in the speaker cavity
The signature is unmistakable once you know it: everything sounds like it is coming through a blanket, the top end is gone entirely, and it happened within a day of the phone being anywhere near water. Not necessarily a dramatic soaking — rain, a humid bathroom, sweat at the gym, a shower shelf and a spilled drink all do it.
The fix is a low tone at full volume with the speaker facing down, run for thirty seconds, twice, wiping the edge between runs. The full method is here, and it works in about two minutes. Do it the same day if you can: while the water is liquid it can be pushed, and once it dries it leaves behind whatever it was carrying as a solid.
2. Lint and dust packed into the grille
This is the slow one, and it is the answer for most people whose phone “got quieter with age”. A speaker grille is a set of small holes over a fine mesh, and it lives in a pocket. Fabric fibres, dust and skin oil pack in together and set into a felt that physically reduces how much air can get through.
You can usually see it. Take the case off, get a bright light at a shallow angle across the bottom edge, and look into the holes: a clean grille shows dark, even openings, and a blocked one is grey and matted. Vibration cycles shake the loose material out; anything genuinely compacted needs a soft dry brush. What it does not need is anything metal or pointed pushed into the holes.
3. The case
Absurdly common and instantly testable: take the case off and play something. If it sounds noticeably better, the case was the problem all along.
- A cutout that does not line up. Third-party and cheap cases frequently sit a millimetre off, and a millimetre over a speaker slot is most of it.
- A thick lip around the bottom edge that turns the speaker output into a tunnel.
- Debris trapped between case and phone. Everything that gets into a case stays in a case, and it accumulates directly over the grille.
- A folio flap lying across the earpiece slot during calls.
4. A software setting you forgot about
Free to check and occasionally the whole answer.
- Is a Bluetooth device connected? A car, a speaker in another room, earbuds in a bag. The phone is playing perfectly — somewhere else.
- Is there a volume limit set? Both iOS and Android ship hearing-safety caps that can be enabled and then completely forgotten.
- Is an EQ or sound profile on? A setting chosen once for headphones applies to the speaker too and can gut the treble.
- Is media volume actually up? Ringer volume and media volume are separate on both platforms, and the buttons change whichever the phone thinks you mean.
- Has it been restarted this month? Audio routing does occasionally get stuck, and a restart is thirty seconds.
5. Only one speaker is blocked
Your phone has at least two speakers: the main one on the bottom edge and the earpiece at the top, which doubles as the second stereo channel. If one is blocked, everything sounds thin and off-balance without sounding obviously broken, and it is easy to misread as “the phone is quieter now”.
Play audio through each one separately and compare. CleanWave has this as a built-in test — top speaker, then bottom, one tap each — and how to test your speakers walks through doing it by hand. It is worth ninety seconds because it changes what you do next: one blocked speaker is a cleaning job, and both quiet in the same way is usually something on this list further up.
6. Damage, and how to recognise it
The word “muffled” is doing important work in all of the above. Muffled means quiet, dull, lacking top end — the sound is intact but reduced. That is a blockage.
These are different symptoms and they mean something else entirely:
The five-minute pass
If you want to just do the thing rather than diagnose it: take the case off, wipe the edges, run a cleaning cycle at a low frequency with the speaker facing down, brush the grille lightly with a dry soft brush, run one more cycle, then test the top and bottom speakers separately. That sequence resolves the large majority of muffled phones, and the ones it does not resolve are the ones worth taking to a shop.