How to check the loop microphone on the Xiaomi Redmi phone: working methods of 2026

The loop microphone in Xiaomi Redmi smartphones is a minor module that often goes unnoticed until it stops working, and it's responsible for noise reduction during calls, improving the quality of voice recording in instant messengers, and even activating voice assistants. But how do you know that the problem is in this module, and not in the main microphone or software failure?

In this article, we will discuss 7 Proven methods of diagnosing a loop microphone on Redmi 9/10/Note 11/12 and other models, including tests through standard tools MIUI, Third-party apps and even physical checks, you’ll learn how to tell a microphone malfunction from firmware problems, why it might be bugged after an update, and what to do if the sound is only lost in specific apps (like WhatsApp or Telegram).

Important: The loop microphone is usually located at the bottom of the case (near the charging connector) or on the back (in models with dual microphones), its failure is not always obvious - sometimes it just starts to suppress noise worse, rather than stop working completely.

1.What is a loop microphone and why you need it in Xiaomi Redmi

The loop (or secondary) microphone in Xiaomi Redmi performs three key functions:

• 🎤 Noise suppression during calls - the main microphone catches the voice, and the loop "cuts off" extraneous sounds (wind, street noise).
• 📱 Improvement of recording quality in messengers (Viber, Zoom) due to stereo effect.
• 🔊 Activation of voice commands (for example, for Google Assistant or Alice from Yandex).

On most Redmi models (such as the Redmi Note 10 Pro or Redmi 12), the loop microphone is located:

• ⚡ In the lower part of the body (near the speaker and USB-C).
• 📱 On the back panel (in models with a double microphone, for example, Redmi). K50).

If this microphone fails, you may encounter:

• 🔇 The interlocutor does not hear you when calling (voice is deaf, a lot of noise).
• 🎥 Videos on TikTok or Instagram are recorded with strong echoes.
• 🤖 The voice assistant doesn’t respond to commands the first time.

Method 1: Testing through a standard test MIUI (no-apps)

The fastest way to check a loop microphone is to use built-in diagnostics. MIUI. It is available on all Xiaomi Redmi models, starting with the MIUI 11.

Instructions:

1. Open the phone app and dial the combination: ##4636##.
2. In the menu that opens, select Phone Information.
3. Scroll down and find Microphone Testing (or Audio Test in English firmware).
4. Press Start Test and speak to the microphone, and the system will show the signal strength for the main and loop microphones.

What do the results mean?

⚠️ Warning: If the loop microphone doesn't show the signal at all, but the main one is working, there's a problem in the hardware (the plume is damaged or the microphone itself). If both microphones are silent, check the sound settings or restart the phone.

Make sure your phone is not in silent mode.

Turn off the Bluetooth headphones.

Close all applications that use the microphone (Zoom, Discord)

Check if the microphone hole is covered with a cover or film-->

Method 2: Testing by bell (noise reduction check)

This method helps you identify problems with the loop microphone that you don't see in the diagnostics. You'll need a second phone.

How to run the test:

1. With Xiaomi Redmi, call another phone.
2. During the conversation, tap your finger on the area of the loop microphone (the lower part of the case).
3. If the person hears the knock clearly, the microphone works, and if the sound is muffled or not, there is a problem with noise cancellation.

Additional checks:

• 🌬️ Blow into the microphone – if the interlocutor hears a strong noise, then the noise cancellation does not work (the fault of the loop microphone).
• 🎶 Turn on music next to the phone – if the interlocutor barely hears it, the microphone is serviceable.

If the loop microphone does not suppress noise, but the main one works, the problem may be:

• 🛠️ Pollution of the microphone hole (dust, moisture).
• 🔧 Damage to the plume (for example, after a phone drop).
• 📱 Firmware failure (especially after update) MIUI).

💡

If during the test the interlocutor complains of echo, try to turn off the function Voice Improvement in call settings (Settings) → Annexes → Phone. → Improving voice).

Method 3: Verification through applications (Microphone Test, Voice Recorder)

Third-party applications allow you to test the loop microphone in more detail, including recording and analyzing frequencies.

• 📱 Microphone Test (by Smart Tools) – shows the signal graph from each microphone.
• 🎤 Voice Recorder (by Sony) – allows you to record sound and listen to it for noise.
• 🔊 SoundAbout – for forced switching between microphones.

Instructions for Microphone Test:

1. Install the app from Google Play.
2. Open it and select the Microphone Test.
3. Speak to your phone and watch the green bar (main microphone) and the blue bar (loop).
4. If the blue band does not respond, the microphone is faulty.

For more accurate diagnosis, use Voice Recorder:

1. Write down 10-15 seconds of speech.
2. Listen to the recording in the headphones – if you hear extraneous noises or the voice sounds “far away”, the loop microphone can not cope with noise cancellation.

⚠️ Note: Some apps (such as WhatsApp or Zoom) may only use the main microphone. If the problem is only there, check the microphone settings inside the app itself.

Method 4: Physically inspecting the microphone (visual examination)

Sometimes the loop microphone stops working because of mechanical damage or contamination.

• 🔍 Microphone hole (usually near the microphone) USB-C) — It should not be covered with dust or film.
• 💧 Traces of moisture – if the phone fell into the water, the microphone could oxidize.
• 📱 dents on the body - after the impact could damage the plume.

How to clean the microphone:

1. Take a toothpick or a soft brush.
2. Remove the dust from the hole (do not press hard!).
3. Use silica gel to remove moisture (put your phone in a bag for 12 hours).

If the microphone does not work after cleaning, the problem may be:

• 🔌 Disconnected plume (requires disassembly of the phone).
• 🛠️ Faulty microphone module (replacement required).
• 📱 Failure of the sound controller (will help reset settings or flashing the flashing).

💡

If the phone falls or gets wet, the loop microphone is more likely to fail than the main one, due to a more fragile design.

6. Method 5: Verification through the Engineering Menu (for advanced)

The Engineering Mode allows you to test the microphone at a low level, and be careful, if you make the wrong settings, you can disrupt the phone.

How to open the engineering menu on Xiaomi Redmi:

1. Open the Phone app.
2. Dial: ##36446337## (for MTK) or #4636### for Snapdragon).
3. Go to the Hardware Testing → Audio section.
4. Select Microphone Test and check both channels (Main Mic and Loopback Mic).

What to do if the engineering menu does not open:

• 📱 Make sure you have global firmware (on Chinese versions) MIUI codes may not work).
• 🔧 Try the alternative code: ##284## (Mic test for some models).
• 🛠️ If nothing helps, use the app. MTK Engineering Mode from Google Play.

⚠️ Note: Do not change the Audio Gain or Noise Suppression settings on the engineering menu unless you are sure of their meaning.

7. Method 6: Diagnostics via PC (for accurate verification)

If you suspect a hardware malfunction, you can check the microphone through the computer.

• 📱 Cable USB-C/USB-A (original).
• 💻 Audacity (free) program).
• 🔊 Headphones (for monitoring).

Step-by-step:

1. Connect Redmi to your PC and select File Transfer mode.
2. Install Audacity and open it.
3. In the recording settings, select your phone as the sound source.
4. Press Record and speak to the microphone. Audacity should display two waves (if there are two microphones).
5. If one of the waves is missing, the loop microphone does not work.

Additional tests in Audacity:

• 📊 Use Analysis. → Show spectrum to check frequency response, if the graph is missing high frequencies (3-8 kHz), the microphone is damaged.
• 🔊 Turn on Monitoring (button with headphones) – if distortions are heard, the problem is in the hardware.

💡

Connection via PC is the most accurate way of diagnosis, as it allows you to see the signal in a “raw” form, without processing. MIUI.

Method 7: Checking after Update MIUI (If the microphone stops working)

A common cause of malfunction of the loop microphone is a failure after updating the firmware.

• 📱 Driver conflict (especially on custom firmware).
• 🔧 Core errors MIUI (for example, in versions MIUI 13-14 were audio bugs).
• 🛠️ Incorrect sound settings after resetting.

How to get back to work:

1. Go to Settings → About Phone → System Update and check the relevance of the firmware.
2. If the update didn’t help, reset settings (Settings) → Additionally. → Reset settings), but do not delete data.
3. For models on Snapdragon try to roll back to the previous version MIUI via Fastboot.

If the microphone stopped working after the update MIUI 14 on the Redmi Note 11/12, Try to disable the “Smart Noise Canceling” function in call settings – this temporarily solves the problem until the next update.

⚠️ Note: If resetting your settings didn’t help and the microphone doesn’t work only in specific apps (like Instagram), clear the cache of those apps (Settings) → Annexes → [Name of name] → Warehouse → Clear the cache).

FAQ: Frequent questions about Xiaomi Redmi loop microphone