How to clean the microphone in Xiaomi Redmi Note 7: from dust, dirt and moisture

Have you noticed that your caller is getting worse when you're on the phone, and voice messages are being recorded with noise? The reason most often lies in the contaminated microphone of the Xiaomi Redmi Note 7. Dust, pile from your pocket or moisture can block the sensitive membrane, which causes the device to stop correctly picking up sound. In this article, we will discuss how to clean the microphone yourself without risking damage to the phone - from simple methods with a vacuum to disassembling the case for deep cleaning.

It's important to understand that the microphones in Redmi Note 7 are not only located in the bottom of the body (main), but also next to the front camera (for noise reduction). If the problem with sound only occurs during conversations, the bottom microphone is to blame. If both voice search and video recording work with interference, you will have to check both, we will consider cleaning each of them, and we will give recommendations for prevention and elimination of the consequences of fluid intake.

Signs of a dirty microphone: how to know if it’s time to clean

Before you start cleaning, make sure the microphone is the problem, not a software failure or a plume damage.

• 🔊 The interviewer complains that your voice sounds muffled or intermittent, as if you are speaking through cotton.
• 📱 When recording voice messages in WhatsApp or Telegram, background noise appears, crackling.
• 🎤 The built-in Dictaphone app captures sound with distortions, although the speakers work normally.
• 📹 Videos taken on a phone contain a silent or completely absent sound despite the microphone being turned on.

If one of these is the same, it's time to act, but first rule out software reasons: restart your phone, check the settings in Settings → Sound, and turn off noise reduction (if it's on). If the problem persists, start cleaning.

⚠️ Warning: Don't confuse mic pollution with speaker damage. If you don't hear well, it's the speaker, not the microphone.

Method 1: Dry cleaning without disassembly (for mild contaminants)

If the microphone is clogged with dust or pile, try removing dirt without opening the case.

You'll need:

• 🧹 Soft brush (for example, for makeup) or a new toothbrush with soft bristles.
• 💨 A container with compressed air (can be replaced with a vacuum cleaner with a blowout mode).
• 🔦 Flashlight (for lighting microphone holes).

Step-by-step:

1. Turn off the phone and get it out. SIM-Memory card/card to avoid static discharge.
2. Point your flashlight to the bottom of the Redmi Note 7, and you’ll see two small holes on the sides of the USB-C connector.
3. Carefully walk the brush through the holes, moving from center to edge. Don't push, the bristles should only touch the surface slightly.
4. Holding the can of compressed air vertically (to prevent leakage of liquid!), with short presses (1-2 seconds), blow the dust out of the holes. The distance to the phone is 5-7 cm.
5. Repeat the procedure for the upper microphone (near the front camera).

Is the phone off?|Whether removed SIM-card?|Do you use a soft brush?|Do you keep your distance when blowing air?|Checked both microphones?-->

After cleaning, turn on your phone and check the sound quality. If the problem persists, move on to the next method.

⚠️ Warning: Never use wet wipes or cotton swabs to clean the microphone! pile can get stuck inside and moisture can corrode the contacts.

Method 2: Deep cleaning with partial disassembly

If dry cleaning doesn't work, you'll have to remove the back cover of the Redmi Note 7 to get to the microphones, a technique that requires care, but even a beginner can do it.

Tools required:

• 🔧 Plastic mediator or special spatula for disassembling phones.
• 🔩 Cross screwdriver (size) PH00).
• 🧲 Magnetic mat or screw container (so as not to lose).
• 🧴 Isopropyl alcohol (90% or higher) and cotton-coated discs.
• 🔍 Lupa (optional, to inspect contacts).

How to Disassemble Redmi Note 7:

1. Turn off the phone and remove the tray for SIM-map.
2. Heat the back cover with a hair dryer (60-70°C) for 1-2 minutes to soften the glue.
3. Insert the mediator into the gap between the lid and the body (start at the bottom corner) and gently lead along the perimeter, snapping the latches.
4. After removing the lid, turn away 12 screws fixing the metal plate (they are of different lengths - remember the location!).
5. Disconnect the battery plume to avoid short circuit.

Now you'll see two microphones: the bottom one (near the USB-C connector) and the top one (under the front camera), clean them with a cotton swab dipped in isopropyl alcohol, and the movements should be light, without pressing, and if the microphones have a safety net, remove it with tweezers and rub the membrane with alcohol.

After cleaning, let the parts dry for 10-15 minutes, then assemble the phone in reverse order. Turn on and check the sound.

Never cleaned |1 times a year |Every 6 months |Only when problems arise-->

Method 3: Eliminating the effects of moisture

If the Redmi Note 7 was in water or rain, the microphone could oxidize or become plaque, in which case a routine cleaning won't help - special measures are needed.

Signs of moisture intrusion:

• 💧 On the screen appears a notification of moisture in the connector USB-C (even if it's dry).
• 🔇 The microphone is not working or is wheezing.
• 🔋 The phone discharges quickly (moisture could damage the battery).

What to do:

1. Turn off the phone immediately and remove the battery (if possible) to prevent short circuits.
2. Place the device in a silica gel container for 24 to 48 hours, and rice doesn't work, it absorbs moisture too slowly.
3. After drying, take the phone apart (as in Method 2) and examine the microphones. If there is white plaque on the contacts, it is oxidation.
4. Remove the oxidation with a cotton swab dipped in isopropyl alcohol. Use an eraser (carefully!) for persistent stains.
5. If the microphone doesn’t recover, it will have to be replaced. The Redmi Note 7 will fit the original microphone with the article Xiaomi MDY-11-EM (bottom) or MDY-11-ET (top).

⚠️ Warning: Don't use a hair dryer to dry the microphone! hot air can warp the membrane or melt the protective mesh.

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If the phone doesn't turn on after getting moisture, don't try to charge it right away.Let it dry for at least 24 hours - even if you can't see the moisture out there, it could have stayed under the screen or on the board.

How to protect the microphone from pollution

To avoid having to clean the microphone every few months, follow the following simple rules:

• 📵 Do not carry your phone in your pocket with coins, keys or fuzzy fabrics (such as a fleece).
• 🌧️ Avoid using the Redmi Note 7 in rain or in high humidity (e.g. in the bathroom).
• 🎧 Use a headset with an external microphone for calls – this will reduce the load on the built-in microphones.
• 🔄 Dry cleaning every 2-3 months (Method 1), even if there are no problems with the sound.

If you are often in dusty conditions (such as construction or workshop), consider buying a dust-proof case.

• Cases with rubber plugs for connectors (for example, Spigen Rugged Armor).
• Films with hydrophobic coating (protect from moisture and fat).

It is also useful to turn off the noise reduction function in call settings if it is on by default. Sometimes the MIUI sound processing algorithms degrade the voice quality, creating the illusion of a microphone malfunction. To turn off: Settings → Sound → Call quality → Noise cancellation (off).

What to do with cleaning the microphone: common mistakes

Many users are doing even more damage to the phone in an attempt to clean the microphone, and this is something that is strictly forbidden:

• 🧼 You use soap, detergents, or household chemicals, and they leave a film that attracts dust.
• 🔥 Warm up the microphone with a lighter or on a stove, and it melts plastic parts and membranes.
• 🧻 Puncture the microphone holes with needles, toothpicks or paper clips, the risk of damaging the membrane is 99%.
• 💦 Wash the microphone with water or alcohol under pressure, the liquid will get inside the body.
• 🧲 Use magnets to clean the contacts, which can demagnetize the speaker or damage the chips. NFC.

If you have already made one of these mistakes, turn off your phone immediately and contact a service center, for example, after getting soapy water, you may need to completely flush the board in an ultrasonic bath.

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The most common cause of microphone failure is mechanical damage to the membrane when cleared with sharp objects, and even a small scratch can render the microphone inoperable.

When is the time to bring your phone to service?

Not all microphone problems can be solved by yourself.

• 🔧 After cleaning, the microphone does not work, but the speakers are working (possibly the plume has gone away or the microphone has burned down).
• 🔥 On the motherboard, traces of burns or bloated capacitors are visible.
• 💧 The phone has been in salt water (for example, the sea) – requires a special washing.
• 🔊 Sound problems are accompanied by overheating, spontaneous reboots or failure of other sensors (for example, a gyroscope).

The cost of replacing the microphone in Redmi Note 7 service centers is from 800 to 1500 rubles (depending on the microphone model and region). If the phone is warranty, do not disassemble it yourself - this will void warranty obligations.

To find the official service center Xiaomi go to the website mi.com/ru/service And enter your city. Before you visit, check if they're working with a Redmi Note. 7 — Some centers refuse to repair outdated devices.

FAQ: Frequent questions about cleaning the microphone