The problem of not having sound when talking or recording video on Xiaomi and Redmi smartphones is common enough and can be caused by software failure and physical damage. When the interlocutor does not hear you and the voice recorder writes silence, the first thing to do is to eliminate software locking of the device. In the MIUI or HyperOS operating system, there are many layers of privacy protection that can automatically disable access to the microphone for individual applications or the system as a whole.
In most cases, the user does not need to carry the gadget to the service center, since the solution lies in the depth of privacy settings or permissions. Hardware breakdown is less common than software conflict, so you should not panic ahead of time. In this article, we will discuss in detail all possible ways to activate and diagnose the microphone, from simple switches to complex system tests.
You have to understand that today's smartphones have multiple microphones: the main one (bottom), the additional one for noise reduction (top), and the front one for video calls. If only one of them stops working, it can indicate a specific problem with a particular module or application using this particular sensor.
Basic check of physical locks and accessories
Before you get into the bars of the system menu, you should rule out the most trivial but often ignored reasons. Many Redmi Note or Xiaomi Mi models use protective cases that can cover the microphone hole. Visually, this may be invisible, but dense silicone or glass can silence almost all of the sound. Remove the case and try to record a voice message again.
Also, look for protective films pasted on the back panel or screen in the area of the speaker. If the film has moved away or has a thick layer of glue in the area of the microphone hole, the sound will be distorted or lost altogether. Clean the microphone mesh with a soft dry brush, as dust and pile from the pocket often clog technical holes.
⚠️ Warning: Do not use sharp objects such as needles or toothpicks to clean the microphone.You risk piercing the membrane of the sensor, after which recovery will only be possible by replacing the plume.
If you use wired headphones or a headset, the problem may lie in them. Check if the sound has switched to an external device. In the audio settings, sometimes the Bluetooth profile remains active, even if it is turned off or far away. Turn off Bluetooth completely and remove the headphones from the headphone jack to check the built-in microphone.
Configure permissions for applications in MIUI and HyperOS
The most common reason the microphone doesn’t work in a particular app (like WhatsApp, Viber or Instagram) is the lack of appropriate permission.The Xiaomi shell Android operating system strictly controls access to personal data.If you accidentally clicked “Disable” the first time you started the program, it will no longer be able to use audio input.
To fix this, go to Settings → Apps → All Apps. Find a problem app (like messenger) and click on it. From the menu that opens, select App Allowances (or simply Permissions), find the Microphone list and set the switch to Allow or Always Allow.
There is also a global switch that can block access to all applications at once. It is located in Privacy Protection → Permissions Management → Microphone. This displays a list of all programs that have ever requested audio access. Make sure the application you need is not marked with red or a ban icon.
☑️ Permit verification
Importantly, newer versions of MIUI 14 and HyperOS have Empty Permissions, so if you choose this option, the app will “think” that there is access, but it will actually receive an empty signal.
Use of permission manager and the function "Privacy Protection"
The MIUI shell has an advanced security management tool called Permission Manager, which allows you not only to grant permissions, but also to see the history of applications accessing the microphone, and if the program accesses the microphone in the background when you are not using it, the system can automatically block this action.
To check, go to Settings → Privacy Protection → Special Permissions → Turn on the microphone. Here you will see a list of applications that are authorized to use audio input. If the desired application is not in the “Allowed” list, add it manually. You can also set up automatic denial of access for old or rarely used programs.
| Type of permit | Description of action | Recommendation |
|---|---|---|
| Permission. | The app has full access to the microphone at any time. | For messengers and voice recorders |
| Ask | The system will request confirmation at each launch. | For lesser-known applications |
| Banned | Access is completely blocked. | For games and lanterns |
| Only when used | Access is available while the application window is open | The best option for safety |
Note the privacy indicator. When the microphone is active, the green icon lights up in the top right corner of the screen (in the status bar), and if you see this icon when you're not using any audio applications, then some program is secretly recording audio, so you need to check the processes that are running.
What to do if the indicator is constantly burning?
Diagnostics through engineering menu and equipment tests
If the permission settings are fine but still no sound, you need to conduct a deep hardware diagnosis. There is a hidden CIT (Customer Information Test) engineering menu in Xiaomi and Redmi smartphones designed to check all the device modules, and this is the most reliable way to know if the microphone is physically working.
To enter the test menu, open the Phone app and enter the combination ##6484##. If the code is entered correctly, the test menu will open. In the list, find the Microphone or Microphone item. There are usually several of them: Main Mic (main), Top Mic (top) and Headset Mic (headset).
The sequence of actions in CIT:
1. Select "Microphone" option.
2. Press the "Start Recording" or "Start" button.
3. Speak into the microphone for 5-10 seconds.
4. Press "Stop" and listen to the tape.
5. If you can hear yourself, the microphone is in good working order.If the test only hears cracking, hissing or silence, it is a direct sign of hardware malfunction, in which case the software methods (reset, flashing) will not help, and the intervention of a wizard is required.
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If there's sound in the CIT test and there's no sound in the applications, the problem is 100% in the software conflict or the settings of a particular application. If there's no sound anywhere, the problem is hardware.
Elimination of software conflicts and resetting of settings
Sometimes errors accumulate in the system that block the audio drivers. This can happen after a failed MIUI update or installing a "heavy" third-party launcher. The first step is to switch the audio profile. Go to Settings → Sound and Vibration → Sound quality and effects (the path may vary depending on the model) and try changing the equalizer or disabling Dolby Atmos if it is on.
If simple methods don’t help, reset your application settings. Go to Settings → Apps → All Apps → Three dots at the top → Reset your application settings. This action will return all permissions and system audio settings to factory values, but won’t delete your personal files, photos or contacts.
⚠️ Note: Before performing a full Hard Reset, be sure to back up your data to the Mi Cloud or your computer, as all information will be deleted.
In extreme cases, if nothing helps, it may be necessary to flash the device through the computer using the Mi Flash Tool utility.This is guaranteed to eliminate any software errors, but requires certain skills.
Possible hardware malfunctions and their symptoms
When software methods are exhausted, it remains to consider a physical breakdown. The microphone on the Redmi and Xiaomi boards is a miniature module that often fails after falls or moisture. Even if the phone has IP water protection, over time, the leakage is broken, and the oxidation of the contacts leads to failure.
Main signs of breakdown:
- 🔇 Complete silence when recording voice in the recorder, although the activity indicator is on.
- 📉 The interviewer hears you very quietly, as if you were a kilometer away, even in silence.
- 📼 The recording contains strong distortion, crackling or "robotic" voice.
- 🔄 The microphone only works in a certain position of the phone (for example, if you press the bottom of the finger).
Often the problem is not with the microphone itself, but with the plume connecting the lower board to the motherboard, and on plastic models, the plumes can move away when they are impacted, and in such cases, the master simply needs to change the connector or replace the plume, which costs less than replacing the microphone.
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If the CIT test shows no sound, and cleaning the holes did not help - you need to replace the microphone module or the bottom plume in the service center.