How to Clean the Speaker on Xiaomi Redmi Note 9 Pro: From Dust to Serious Pollution

Xiaomi Redmi Note 9 Pro is one of the most popular mid-range smartphones, but even it is not immune to the problem of clogged speakers. Over time, dust, villi from your pocket or particles of skin fat will accumulate in the grilles, leading to muted sound, wheezing or complete disappearance of bass. In this article, we will analyze 5 proven cleaning methods that will return your phone a clear sound – from fast methods with improvised means to deep cleaning with disassembly.

It is important to understand that the speakers of the Redmi Note 9 Pro have vulnerabilities: the bottom speaker (main) is more likely to suffer from mechanical contamination, and the top (conversational) from moisture and fat. We will not advise “blow with your mouth” or use wet wipes – these methods only exacerbate the problem. Instead, focus on safe techniques recommended by Xiaomi service engineers.

If the sound is not restored after cleaning, the problem may be damage to the speaker membrane or detachment of contacts, in which case professional repairs will be required, but in 80% of cases it is the dust that can be dealt with independently.

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

The first symptoms of a speaker contamination are often attributed to "firmware bugs" or "bad connection," and in fact, if you notice any of these signs, it's time to clean up:

• 🔊 The sound became quieter, especially at low frequencies (bass "disappears")
• 🎵 There were wheezing or crackling when playing music
• 📞 The interviewer does not hear you when calling (problem with the top speaker)
• 💨 After the phone fell, the sound was distorted (possibly the dust penetrated deeper)
• 🌧️ The phone has been in the rain or in a wet room (oxidation of contacts)

On the Redmi Note 9 Pro, the bottom speaker is located next to the USB-C connector, so it actively draws dust there when charging. The top speaker (aka the conversation microphone) suffers from skin fat if you often put the phone to your ear. It is simple to check for contamination: point the flashlight at the speaker grille - if you see a gray plaque or villi, it is time to act.

⚠️ Warning: If the sound is completely gone after a phone drop or fluid hits, cleaning won't help, and then you need to be diagnosed for a plume break or short circuit.

Method 1: Dry brushing with a toothbrush (for surface contaminants)

This is the most gentle method, and it's the most effective for regular prevention, and you'll need a soft bristling toothbrush (new or baby's, better) and good lighting, and the rule is, don't press the grille so you don't damage the speaker's membrane.

Algorithm of action:

1. Turn off your phone to avoid static electricity.
2. Carefully sweep the speaker along the grille (not across) 5-7 times.
3. For the upper speaker, use rotational movements - so fat deposits are better removed.
4. Remove the knocked dust with a dry paint brush or compressed air (keyboard cleaner).

This is effective at removing dust, villi and fine debris, but it won't deal with old fat or dust that has penetrated deep into the case. If the sound hasn't improved after cleaning, move on to the next method.

Method 2: Cleaning with tape or sticky tape (for villi and large debris)

If you have cloth villi or small particles stuck in the speaker, you can extract them using tape or paint tape, a method that is suitable for the Redmi Note 9 Pro, since the grilles of its speakers have large enough holes (unlike the flagship models of Xiaomi).

Step-by-step:

1. Cut a small piece of scotch (width 5-7 mm).
2. Apply the sticky side to the speaker grille and easily press (do not press!).
3. Carefully pull the tape on yourself - the garbage will remain on the tape.
4. Repeat 2-3 times, each time using a new piece of scotch.

For the top speaker, it's better to use a narrow tape (for example, for cigarettes) to avoid hitting the microphone, which is not suitable for removing dust - only for large debris. If after the procedure the sound still wheezes, then the pollution is deeper.

⚠️ Warning: Do not use stationery tape - its glue can remain on the grille.Optimally, paint tape or tape for sealing boxes (with paper base).

💡

If there is no scotch on hand, take the sticky side of the fruit sticker or packaging - it is soft enough and will leave no traces.

Method 3: Vacuum cleaning (for deep dust)

If the dust has penetrated the body through the grille, a conventional brush will not help, in which case they use a mini-vacuum cleaner (for example, to clean the keyboard) or a can of compressed air, the main thing is to direct the air flow correctly so that the membrane is not damaged.

How to clean:

• 🌀 Use the minimum power of the vacuum cleaner (or keep it 3-5 cm away from your phone).
• 💨 Keep the compressed air container vertically to avoid the release of liquid (it is in any cylinder!).
• 🔄 Treat the speaker with short pulses (1-2 seconds) so as not to overheat the membrane.

For the Redmi Note 9 Pro, it is especially important not to direct the jet at right angles - this can drive the dust even deeper. Optimal angle: 30-45 degrees relative to the surface of the phone. After the procedure, check the sound - if the wheezing is left, then dust has accumulated on the back of the grille (removal will be required).

Method 4: Ultrasonic cleaning (for severe contaminants)

If the Redmi Note 9 Pro speakers haven't been cleaned for years, the usual methods may not work, and an ultrasound bath will help, but it requires partial disassembly of the phone, which is used in service centers, but can be repeated at home with tools.

What you need:

• 🛠️ Set of screwdrivers (cross-haired) PH00 and plastic mediator)
• 💧 Ultrasonic bath (or jewelry cleaning device)
• 🧴 Distilled water or alcohol (at least 90%)
• 🧲 Magnet for attaching the vibration module

Process:

1. Remove the back cover of the phone (on the Redmi Note 9 Pro it is attached to the latches + glue).
2. Disconnect the speaker plume and carefully remove it from the body.
3. Place the speaker in an ultrasonic bath with distilled water for 1-2 minutes.
4. Dry the speaker for 24 hours in a dry place (you can speed up the process with a hairdryer at minimum power).
5. Put the phone back together.

This method removes 100% of contaminants, including contact oxidation, but requires experience in disassembling smartphones. If you have never disassembled Xiaomi, it is better to contact the service - an error in the assembly can lead to loss of leakage or damage to the plume.

Method 5: Software Diagnostics (if cleaning didn't help)

If the sound is bad after all the manipulations, the problem may not be pollution, but a software failure or hardware malfunction. The Redmi Note 9 Pro has built-in tests to check the speakers:

How to start the diagnosis:

1. Open the Phone app and dial ##4636##.
2. Select Hardware Testing (Hardware Testing).
3. Press Audio and check the performance of both speakers.
4. If the test shows an error (such as Speaker failed), the problem is in the gland.

You can also use third-party apps like Phone Doctor Plus or TestM to check:

• 🔈 Upper and Lower Dynamics separately
• 🎤 Sensitivity of the microphone (if the interlocutor does not hear well)
• 🔌 Audio chain integrity (are there any breaks)

If tests show that the speakers are working, but the sound is still bad, it may be the firmware's fault. Try resetting to factory settings (Settings → About Phone → Settings Reset) or updating MIUI to the latest version.

💡

If after cleaning the sound is not restored, and tests show an error speaker, do not waste time on repeated attempts - contact the service. Self-repair without tools can aggravate the problem.

What not to do when cleaning the speakers

Some folk methods not only do not help, but also are guaranteed to spoil the dynamics.

• 🚫 Blowing with the mouth - saliva falls on the membrane and causes corrosion.
• 🚫 Use wet wipes - water penetrates the body and oxidizes the contacts.
• 🚫 Puncture holes with a needle - it tears the membrane of the speaker.
• 🚫 Clean with alcohol without disassembly - it dissolves the glue that holds the grille.
• 🚫 Use a powerful vacuum cleaner - it can tear off the membrane.

Also, don’t trust tips like “wash the speaker with water” or “knock on the phone” – these are myths that lead to irreversible damage. If you doubt the method, you should contact Xiaomi’s service center.

⚠️ Note: On the Redmi Note 9 Pro, speakers do not have protection by standard IP68, If the phone has been in the rain, dry it for at least 48 hours in rice or silica gel before cleaning.

FAQ: Frequent questions about cleaning speakers