How to increase the volume of the speaker on Xiaomi Mi 9T: from the settings of MIUI to the engineering menu

Why is the speaker on the Mi 9T running too quiet?

Owners of Xiaomi Mi 9T (also known as Redmi K20 in some regions) often face the problem of low volume of the speaker. Even at maximum settings of the interlocutor’s sound, it can be difficult to hear in a noisy environment, the reasons can be both software (MIUI restrictions, incorrect uniformity settings) and hardware (contamination of the speaker, wear of the membrane).

It's important to understand that the earpiece and the louder speaker are different components, the former being optimized for voice (300-3400 Hz) and physically unable to produce the same volume as a multimedia speaker, but there are ways to get the most out of it, from standard MIUI settings to hidden engineering menu settings.

In this article, we'll look at all the current ways to increase the volume of the conversational speaker on the Mi 9T, including secure modifications to system files and proven applications. None of the ways require root rights unless otherwise stated.

1. Check basic sound settings in MIUI

Before digging deeper, make sure the problem isn't with the standard settings. On the Xiaomi Mi 9T with MIUI 12-14, the path to key audio parameters may be different, but the overall logic holds.

Open the Settings → Sound and vibration and check:

• 🔊 Call volume: the slider should be at maximum. On some firmware, it's divided into Melody and Challenge -- check both.
• 🎧 Headphone amplification: Turn off this option if it’s active – it can affect the overall volume.
• 🔄 Adaptive sound: try turning it on/off, and on some devices, it artificially lowers the volume to make it "comfortable.
• 🛠️ Settings of uniformity: in the section Additional → Select Preset "Dynamic" or turn off the uniformity completely.

If the volume hasn’t changed after these manipulations, move on to the next step. Note that on some custom firmware (e.g. Pixel Experience or LineageOS), the path to settings may be different.

2. Cleaning the conversational speaker from dust and debris

One of the most common causes of volume loss is speaker pollution. On the Mi 9T, the speaker is located at the top of the screen (above the display) and over time gets clogged with dust, potassium deposits and fine debris, which physically blocks the vibrations of the membrane, reducing the volume by 30-50%.

How to clean the speaker without breaking the phone:

1. Take a toothpick (not a metal one!) and gently wrap its tip with a wet optics wipe.
2. Walk through the speaker grille with a light movement, without pressing hard. The movements should be parallel to the screen, not deep into the holes.
3. Use a vacuum cleaner with minimal power (or a dryer in cold air mode) at a distance of 5-7 cm to blow out the dust.
4. For final cleaning, you can use alcohol wipes (at least 70% alcohol), but without excessive pressure.

⚠️ Warning: Do not use needles, pins or other sharp objects - they can damage the speaker's protective net. Also avoid getting liquid inside the housing: Mi 9T There is no official protection from water (IP-certification).

If the volume didn't go back after cleaning, it's more of a software problem.

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Before cleaning the speaker, make a test call on the speakerphone and record the sound on the recorder. After cleaning, repeat the test so you can objectively assess the difference.

3.Use of the engineering menu (without root)

Engineering menu (Engineer Mode) is a hidden section of Android where you can fine-tune the parameters of hardware components, including speakers. 9T access to it is opened through USSD-code, but requires caution: incorrect settings can lead to distortion of the sound or even damage to the speaker.

Instructions to increase volume through the engineering menu:

1. Open the Phone app and enter the code: ##36446337## Some firmware may run an alternative code: ##4636###
2. In the menu, select Hardware Testing → Audio.
3. Go to LoudSpeaker Mode (or Receiver is a conversational speaker).
4. In the Value field, increase your current value by 5-10 units (usually the maximum safe value is 160-180). Do not bet more than 200 - this can lead to distortion!
5. Press Set, then Exit and restart the phone.

If the sound becomes hoarse or intermittent after changing the values, go back to the engineering menu and reduce the value by 5-10 units. The optimal balance between volume and quality is selected experimentally.

4.Apps for sound amplification (TOP-3 verified)

If system methods fail, you can use third-party applications. It is important to choose utilities that do not require root rights and do not contain suspicious permissions (for example, access to SMS or contacts), We tested dozens of applications and selected the three most effective for the Mi 9T:

Before installing any application, check the user reviews of Xiaomi Mi 9T - some utilities may conflict with MIUI. We also recommend testing the volume in the headphones: if the sound in them is also quiet, the problem may be in the microphone of the interlocutor, not in your speaker.

⚠️ Warning: Avoid apps that require root rights for "maximum boost of sound." 9T This often causes the speaker to burn out because it's overloaded.

5. Modification of system files (for advanced users)

If you're willing to take risks, you can manually edit the system files that control volume, which requires an unlocked bootloader and a super-user (root) right, but it has the most noticeable effect. We'll look at two options: build.prop and over. mixer_paths.xml.

Method 1: Editing build.prop

1. Install a file manager with root support (such as Root Explorer or Solid Explorer).
2. Go to /system/build.prop and back up the file.
3. Add the following lines to the end of the file: ro.audio.volume.max=100 ro.audio.volume.boost=1
4. Save the changes, restart the phone.

Method 2: Change of change mixer_paths.xml

This file contains hardware volume limits for each speaker: /vendor/etc/mixer_paths.xml or /system/etc/mixer_paths.xml (firmware-dependent).

Find a box with parameters for rx-voice and increase the max values by 10-15%.

<path name="rx-voice">


<ctl name="RX1 Digital Volume" value="84" />




<ctl name="RX2 Digital Volume" value="84" />




</path>

⚠️ Attention: Incorrect editing mixer_paths.xml This can cause a complete loss of sound or looping of the phone on the boot.Be sure to back up through the phone before making changes. TWRP!

If the sound is distorted after the modification, return the original values or restore the file from the backup. Also note that after the MIUI update, all changes will reset.

Backup all important data

Make sure the loader is unlocked

Check for root rights (via Magisk or SuperSU)

Download the original build.prop/mixer_paths.xml kickback

Charge your phone at least 50 times%-->

6 Hardware solutions: replacement of the speaker or repair

If the software methods didn’t help, the problem could be a physical speaker malfunction. On the Xiaomi Mi 9T, the most common hardware causes of quiet sound:

• 🔧 Dynamic wear of the membrane (natural aging after 2-3 years of use).
• 💧 Corrosion of contacts due to moisture (even without complete flooding).
• 🔌 Oxidation of soldered joints on the board (often after falls).
• 🎛️ Sound chip malfunction (less often but requires motherboard replacement).

The cost of replacing the speaker with the Mi 9T in service centers is 800-1500 rubles (depending on the region).

• The original speaker has the article XIAOMI 190410801 (or 190410802 for some revisions).
• To disassemble the phone, a plastic spatula and a sucker will be required (the display is glued).
• After the speaker is replaced, it may be necessary to calibrate the sound through the engineering menu.

If you are not sure of your skills, it is better to contact the service. Poor soldering or damage to the display plume during disassembly can turn into more expensive repairs.

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Before replacing the speaker, check its performance through the test menu: type ##6484## and select Manual Test → Receiver. If the sound in the test is quiet and the headphones are normal, the speaker is faulty.

7.Alternative solutions: headphones, Bluetooth, external speakers

If you can not increase the volume of the speaker, consider alternative ways of making calls:

• 🎧 Wired headphones with a microphone: even budget models (for example, Xiaomi Basic) will give a clearer sound than the built-in speaker.
• 🔗 Bluetooth headset: any model with profile support is suitable HFP (Redmi AirDots and Mi True Wireless Earphones).
• 📞 Loud communication: in noisy places, you can use the main speaker of the phone (but it is inconvenient for long conversations).
• 🔊 External Bluetooth speaker: some models (e.g, JBL Go) support telephone call mode.

For Mi 9T owners, there is another life hack: if you have a smartwatch or a fitness bracelet (like the Mi Band 6/7), you can receive calls through them, the sound will be transmitted to the clock, and the microphone will remain in the phone, while the quality of communication does not deteriorate.

If you make frequent calls in noisy places, consider buying a dedicated noise-cancelling headset (like the Xiaomi FlipBuds Pro) that will not only amplify the sound, but also improve the voice perception for the person you are talking to.

FAQ: Frequent Volume Up questions on Mi 9T