Where is the microphone in Xiaomi Redmi Note 9 Pro: detailed scheme and tips for checking

Xiaomi Redmi Note 9 Pro is one of the most popular mid-range smartphones, but even these devices sometimes have problems with sound. If your interlocutor can’t hear you while calling or voice messages are recorded with noise, the first thing to do is check the microphones. In this article, we will discuss in detail where the microphones in the Redmi Note 9 Pro are located, how they work and what to do if one of them fails.

Many users mistakenly think that there is only one microphone in a smartphone, the one you see next to the main camera. In fact, there are at least three in the Redmi Note 9 Pro, and each one is responsible for its function: the main one for calls, the additional one for noise reduction, and the third one for recording video or voice commands. If you don't know exactly where to look for the microphone, further diagnostic or repair instructions will be useless. So let's start with the most important one, the layout.

How many microphones in the Xiaomi Redmi Note 9 Pro and why they need

The Redmi Note 9 Pro has three microphones, each of which performs its own role:

• 📞 Main microphone – used for voice calls and located at the bottom of the case next to the connector USB-C.
• 🎤 The second microphone (for noise reduction) is located at the top, next to the speaker speaker of the conversation, and it picks up background noises and helps improve the quality of voice during a conversation.
• 📹 Third microphone (for video and voice commands) - located on the back, next to the main camera, used for recording video or activating voice assistant.

This is not unique — most smartphones today have multiple microphones to improve sound quality. However, the Redmi Note 9 Pro has one feature: the second microphone (noise reduction) is often confused with the light sensor because of its tiny size and location near the front camera, which leads to diagnostic errors — users try to clear the wrong hole.

If one of the microphones gets clogged or malfunctioned, it will immediately affect the sound quality. For example, if the main microphone is not working, the person will hear you very quietly or with distortions. If the upper microphone is a problem, you will hear extraneous noises (wind, street hum) during the call. And if the rear microphone is defective, the videos will be recorded without sound or with a strong noise.

Where exactly is the main microphone in the Redmi Note 9 Pro?

The main microphone, which is responsible for voice transmission during calls, is located in the lower part of the case, to the right of the USB-C connector. If you turn the smartphone upside down, the microphone will be:

• 📱 Right of the charging connector.
• 🔊 Left of the main speaker hole (which plays music and notification sounds).
• 🕳️ It is a tiny hole (sometimes barely noticeable), covered with a protective net.

To identify it accurately, take a flashlight and shine a light on the bottom of your smartphone, and you'll see three holes:

1. The big left is the speaker.
2. The little central one is a microphone.
3. The right big one is a USB-C connector.

The central hole is the main microphone, and it's easy to confuse it with the speaker, but the speaker has a lattice with lots of small holes, and the microphone has one or two large holes.

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If the microphone is clogged, do not try to clean it with a needle or toothpick - this can damage the membrane.

Location of the second microphone (noise reduction)

The second microphone, which is responsible for noise cancellation, is located at the top of the smartphone, next to the speaker. If you look at the front panel of the Redmi Note 9 Pro, it is located:

• 📞 Right of the speaker (if you hold the phone vertically).
• 🕳️ It is a tiny hole, almost invisible to the naked eye.
• 🔍 It is often confused with a proximity or illumination sensor, but the microphone has a physical opening and the sensors do not.

To find it, turn on the flashlight and carefully examine the area next to the front camera.

1. Dynamic (a lattice with many holes).
2. Microphone (one small hole to the right of the speaker)
3. Sensor of approach and illumination (no physical holes, only glass surface).

This microphone is important for the quality of calls — it picks up background noises and helps the smartphone suppress them, and if it clogs or fails, the interlocutor will hear echoes, wind noise or other foreign sounds.

⚠️ Warning: If you notice that the person complaining about noise during the calls, but your voice is clearly heard, the problem is most likely in the upper noise reduction microphone.

Where is the third microphone (for video and voice commands)

The third microphone in the Redmi Note 9 Pro is located on the back, next to the main camera.

• 📹 Video recordings.
• 🎙️ Voice command recognition (e.g. for Google Assistant or Alice).
• 🔊 Improved sound quality when using the rear camera for video calls.

To find him:

1. Turn the smartphone back upwards.
2. Find the main camera unit (four lenses + flash).
3. To the right of the camera block (if you hold the phone horizontally), you will see a small hole – this is the microphone.

This microphone is often clogged with dust, especially if you carry a smartphone in your pocket or without a case. If the video is recorded without sound or with a lot of noise, check it first.

How to check which microphone is not working

If you suspect that one of the microphones in the Redmi Note 9 Pro is faulty, you can make a simple diagnosis:

Record a voice message in the messenger and listen to it|Call another phone and check how you can be heard.|Take a short video and check the sound.|Use a microphone testing app (e.g. Microphone Test)|Try to activate the voice assistant (OK, Google)-->

Here is a more detailed instruction:

1. Primary microphone test: Call another phone, and if the person can't hear you or hears you very quietly, the problem is with the main microphone.
2. Noise reduction microphone test: Call from the street or in a noisy room. If the person hears background noises (wind, voices), the upper microphone does not work.

Microphone test for video:

• Take the video on the main camera.
• If the sound is not there or it is distorted, the problem is in the rear microphone.

You can also use specialized applications for testing microphones, for example:

• 📱 Microphone Test (shows signal strength from each microphone).
• 🎤 Voice Recorder (allows you to record and listen to sound).
• 🔊 SoundAbout (allows you to manually choose which microphone to use).

⚠️ Attention: If the test found that only one microphone was not working, it was likely a physical injury or clogging problem. If all microphones were not working at the same time, it could be a software failure or damage to the motherboard.

What to do if the microphone is not working

If you find that one or more microphones in the Redmi Note 9 Pro are faulty, try the following steps:

1. Microphone cleansing: Use a soft brush or compressed air to remove dust. Do not use sharp objects - they can damage the membrane.
2. Check settings: Make sure the microphone is not turned off in the call settings (Settings → System Applications → Phone → Call settings). Check the microphone permissions in Settings → Applications → Permissions → Microphone.
3. Reset: Reset network settings: Settings → System → Reset settings → Network settings Reset. If it doesn’t work, make a full reset to factory settings (remember to save data!).
4. Software Update: Check for updates: Settings → About Phone → System Update. Sometimes microphone problems are solved after the latest firmware is installed.

Calling the service:

• If nothing has worked, it is possible that the microphone is physically damaged and needs to be replaced.
• Xiaomi will replace the microphone in 1-2 days.

If you want to clean the microphone yourself, follow these rules:

• ✅ Use only soft materials (painting brush, cotton swab).
• ✅ Compressed air should be of low power (no more than 2-3 short presses).
• ❌ Don’t blow with your mouth – saliva can get inside and cause corrosion.
• ❌ Do not use alcohol or liquids – they can damage the membrane.

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If the microphone still does not work after cleaning, do not try to disassemble the smartphone yourself - in the Redmi Note 9 Pro, microphones are soldered to the motherboard, and their replacement requires special equipment.

Frequent questions about microphones in the Redmi Note 9 Pro