How to clean the speaker on Xiaomi Mi 9 SE: from dust to water damage

Xiaomi Mi 9 SE is a compact flagship with great sound, but over time, the speakers of any smartphone get clogged with dust, fibers from pockets or even get exposed to moisture. If you notice that the sound has become muffled, wheezing has appeared or one of the speakers has stopped working altogether, the problem is probably physical pollution. You don't have to disassemble the phone for this: in 90% of cases, the gentle cleaning methods that we will discuss in detail below.

This manual is suitable for prevention (for example, if you often wear the Mi 9 SE in dusty conditions), and for correcting already noticeable malfunctions. We will consider both mechanical methods (using improvised tools) and software tricks for diagnosis. Importantly, the methods are different for the upper speaker (conversational) and lower speaker (multimedia), so read the descriptions carefully.

Before you start, check if the sound deterioration is related to the settings. Go to Settings → Sound and vibration → Sound quality and make sure that the Quiet Sound mode is not activated or the equalizer is not lost to the minimum frequencies. If the problem persists, proceed to clean up.

Signs of a contaminated speaker: when it's time to clean

Bad sound doesn't always mean a break, but here are the key symptoms that indicate a clogging of the Mi 9 SE speakers:

• 🔊 Muffled sound – music and voices are heard, but as if from under the blanket, without clear high frequencies.
• 🌀 Wheezing or crackling when playing - especially noticeable at volume above 70%.
• 🔇 One speaker is quieter than the other in Mi 9 SE Stereo sound, so the difference is clearly heard).
• 💧 The sound “bubbles” after moisture hits (even if the phone hasn’t sunk, condensate can accumulate inside).
• 🕳️ Visible dirt in the lattice – if you shine a flashlight, you can see fibers, dust or skin particles.

If there is a suspicion of hardware failure in addition to contamination (for example, the speaker does not make any sounds or the phone fell into the water), cleaning may not help. In such cases, a diagnosis is required at the service center.

⚠️ Warning: Do not try to blow the speaker with your mouth - moisture from the breath can settle inside and aggravate the problem. Also avoid vacuum cleaners: they create too much tension and can damage the membrane.

Preparation: What will be needed to clean

For safe cleaning of the Mi 9 SE speakers, prepare the following tools and materials:

You might also need a magnifying glass or a flashlight to give you a better idea of the pollution. USB-microscope (stands) ~500₽), It will help you evaluate the cleaning result.

⚠️ Warning: Never use metal objects (needles, pins, knives) - they can scratch the grille or damage the speaker membrane. Also avoid aggressive liquids (acetone, gasoline, glass washing agent).

Method 1: Dry cleaning with toothpick and scotch

This method is suitable for removing fibers, dust and fine debris from the speaker grille, and is the safest and recommended for regular prevention.

Step-by-step:

1. Turn off the Mi 9 SE and place it on a flat surface with the speaker grille upwards.
2. Take a toothpick and gently, without pressing, run it through the grille, putting on visible fibers or dust lumps, and move parallel to the holes, not across, so as not to drive the dirt deeper.
3. Cut a small piece of tape (~5 mm wide), fold it sticky side outwards and press it lightly against the grille. Repeat 2-3 times, each time using a new piece.
4. For the lower speaker (multimedia), repeat the same actions, but be careful - its grille is thinner and easier to bend.

After cleaning, turn on your phone and check the sound. If you have any wheezing, move on to the next method.

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For better effect, use a toothpick dipped in alcohol (but not wet!) the alcohol will evaporate, leaving no moisture, but will help dissolve the fatty deposits.

Method 2: Wet cleaning with alcohol (for fatty contaminants)

If the speaker is clogged with not only dust, but also greasy marks (for example, from hand cream or cosmetics), dry cleaning will not help.

Important: Do not use water or wet wipes based on alcohol with additives! Only pure isopropyl.

Instructions:

1. Turn off the phone and remove it. SIM-card (in case the alcohol gets into the tray).
2. Soak the cotton swab in alcohol and squeeze it off so it is wet, but not wet.
3. Gently wipe the speaker grille in the direction of the holes without pressing. Don't try to stick the stick inside!
4. Let the phone dry for 10-15 minutes in a vertical position (grid down) so that the alcohol completely evaporates.
5. To accelerate drying, you can use a dryer in cold air (keep at a distance of 20 cm, no closer!).

If the sound is better after cleaning, but the wheezing remains, the problem may be deeper - in this case, compressed air purges will help (method 3).

⚠️ Warning: If the speaker gets worse after wet cleaning, or if there's a distortion, it means the alcohol got inside. Immediately dry the phone in rice or silica gel for 24 hours. Do not turn it on until it is completely dry!

Method 3: Purging with compressed air (for deep dust)

This is effective when dirt is stored behind the speaker's bar and you can't see it from the outside. The airflow blows out dust without damaging the membrane. It's important to use a special compressed air can (sold in electronics stores) rather than a household vacuum cleaner or compressor.

Why can't you use a vacuum cleaner?

Unlike a can, a vacuum cleaner creates reverse thrust, which can pull dust deeper into the speaker or even tear the membrane away, and the canister produces short pulses of air that push the dirt out.

How to blow the speaker correctly:

1. Turn off the Mi 9 SE and put it on the table.
2. Keep the spray vertically (do not tilt so as not to splash liquid!).
3. Direct the nozzle of the can at an angle of 45 degrees to the speaker grille, at a distance of 2-3 cm.
4. With short presses (1-2 seconds) blow the speaker. Repeat 3-4 times for each hole.
5. After purging, gently walk along the grille with a dry brush to remove the blown dust.

If you have left wheezing after purging, try combining this method with dry cleaning with a toothpick (method 1).

Method 4: Software Diagnostics Before Cleaning

Before you disassemble the phone or aggressively clean the speakers, make sure that the problem is in them.The Mi 9 SE has hidden tests that will check the audio system.

How to start the diagnosis of speakers:

1. Open the Phone app and enter the combination: ##4636##.
2. In the menu that appears, select Equipment Testing → Audio.
3. Press Speaker Test. The phone will play the sound in turn on each speaker.
4. If one of the speakers is not making a sound or it's distorted, it's a hardware problem. If there's a sound but it's quiet/hreezy, you need to clean it up.

You can also use third-party apps like Phone Doctor Plus (available on Google Play), which not only test speakers, but also microphone, vibration and other components.

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If the test shows that the speaker is not working at all (no sound), cleaning will not help - you need to replace the module.

Method 5: Cleaning after water (emergency measures)

If the Mi 9 SE is caught in the rain, falls in a puddle or has been spilled on it, the speakers may bumble or stop working altogether, in which case immediate action is needed to prevent corrosion.

What to do in the first 30 minutes:

• 🚫 Turn off the phone immediately (don’t press buttons, don’t try to check the sound!).
• 🔋 Extract. SIM-card and memory card (if any).
• 🧻 Wet your phone with a paper towel without rubbing liquid.
• 🌊 Place it in a vertical position (grid speaker down) so that the water drains away.

Further action (after 1 hour):

1. Place the phone in a silica gel bag (in shoe or electronics boxes) for 24 to 48 hours. If silica gel is not available, use uncooked rice (but it is less effective).
2. Don't turn on the phone, even if it's dry, and moisture could have stayed inside.
3. After drying, check the sound. If the speaker is wheezing, gently blow it through with compressed air (method 3).

If the speaker has not recovered after drying, do not try to disassemble it yourself - in the Mi 9 SE, the speakers are soldered to the board, and without experience you risk damaging the plumes.

What not to do when cleaning the speakers

Some “folk” methods can irrevocably spoil the dynamics of the Mi 9 SE.

• 🔥 Heat the phone (with a hair dryer in hot air, in the oven, on the battery) - this deforms the membrane and plastic parts.
• 💦 Wash the speaker with water or soap solution - moisture will remain inside and cause corrosion.
• 🔪 Use sharp objects (needles, knives, paper clips) - they will pierce the membrane or scratch the grille.
• 🧲 Use magnets – speakers contain metallic parts that can magnetize and distort sound.
• 🧹 Vacuum the speaker - strong traction will damage the membrane or pull dust deeper.

Also, you shouldn't disassemble the phone without experience. In the Mi 9 SE, the speakers are attached to the glue and connected to the board with thin plumes - one wrong movement, and the sound will disappear forever.

FAQ: Frequent questions about cleaning speakers