How to increase the volume of the auditory speaker on Xiaomi Mi 9T: from standard settings to deep modifications

The audio speaker on the Xiaomi Mi 9T (also known as the Redmi K20 in some regions) is often a source of frustration for users, especially when talking on the phone or playing media through external speakers. Even at maximum volume, the sound can appear quiet, muffled or distorted, both in the hardware limitations of the model and in the software "clamps" from the MIUI, which Xiaomi installs to protect the speakers from overload.

In this article, we’ll look at 7 working ways to turn up the volume, from secure settings in the smartphone interface to deep modifications requiring superuser rights (root), each with step-by-step instructions, warnings about possible risks and an explanation of why it works (or doesn’t work) on the Mi 9T. Importantly, not all solutions are equally effective – some give a 10-15% increase, others are able to double the volume, but with a risk to the hardware.

Before you make any changes, check if the problem is temporary. For example, after upgrading MIUI to version 14.0.5.0 and higher, many users have noted a decrease in the volume of the speaker due to changes in the audio drivers, in which case a rollback to the previous firmware or waiting for a patch from Xiaomi can help.

1. Check basic sound settings in MIUI

Start with the obvious – make sure that the problem is not the wrong settings. On the Xiaomi Mi 9T, there are several “hidden” options that can affect the volume of the speaker:

• 🔊 Mode "Sound amplifier": go to Settings → Special facilities → Sound amplifier. Turn on the option and set up sliders for media and conversation. This mode is for people with hearing impairments, but it can add a new version. +5-10% volume.
• 🎧 Disabling "Adaptive Sound": in Settings → Sound and vibration → Adaptive sound deactivate the function. It automatically adjusts the volume to the ambient noise, but sometimes it doesn't work properly.
• 📞 Network profile check: press the volume button during the call and make sure that the "Speak" profile is selected (if necessary). 9T Bug with automatic switching to "Phone" can reduce the volume.

It’s also worth checking whether Do Not Disturb or Quiet in the notification curtain is activated, which can limit volume even at maximum settings on the menu.

⚠️ Warning: If these parameters change, the sound becomes distorted (wheezing, crackling), return the settings to the original state.This may indicate hardware problems with the speaker or audio chip Qualcomm Snapdragon 730, which is used in the Mi. 9T.

2.Use of the Engineering Menu (MTK Engineer Mode)

The engineering menu is a hidden tool for diagnosing and fine-tuning the hardware components of a smartphone. On the Xiaomi Mi 9T, it lets you manually adjust volume levels for different scenarios (calls, media, alarm clock).

To open the engineering menu:

1. Open the Phone app.
2. Enter the code ##36446337## (or alternative #4636###).
3. Go to the Hardware Testing → Audio section.

You'll see a few tabs on the Audio menu, and we're interested in:

• 📞 Normal Mode – Volume setting for regular calls.
• 🎵 Headset Mode – for headphones (does not affect the speaker).
• 🔊 LoudSpeaker Mode – loud communication and multimedia.

For each mode, you can change the Level and Value settings. For example, for LoudSpeaker Mode, try increasing the Max Vol from 160 to 180-200. Don't exceed 220 - this can knock the speaker out!

⚠️ Warning: After changes to the engineering menu, restart your smartphone. If the sound becomes distorted or background noise appears, reset the factory settings through the same Audio section → Reset.

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Before you change the parameters in the engineering menu, write down the initial values on paper or take a screenshot, which will help you quickly get it back to the bottom of the problem.

3. Modification of the file mixer_paths.xml (root)

For advanced users who are ready to get root rights, there is a way to increase the volume by editing the system file. mixer_paths.xml. This file contains audio chip configurations and volume limits for different scenarios. 9T He's on the way:

/vendor/etc/mixer_paths.xml

To change it:

1. Get root access (for example, through Magisk).
2. Use a root-enabled file manager (such as Root Explorer or Solid Explorer).
3. Find the file. mixer_paths.xml And back it up.
4. Open the file in the text editor and find the lines with the parameters: <path name="speaker"> <ctl name="RX1 Digital Volume" value="84" /> <ctl name="RX2 Digital Volume" value="84" /> Increase the value from 84 to 90-95 (no higher!).
5. Save the changes, restart the smartphone.

This method can increase volume by up to 30-40%, but it requires caution, and if you make the wrong changes, you'll lose sound or damage the system.

4.Apps for amplification of sound (without root)

If you don't want to risk system files, you can use third-party apps from Google Play, which are software-based audio processing, and can increase volume with amplification algorithms and equalizer. 9T:

• 🎛️ Volume Booster GOODEV — It's a simple booster with presets for different scenarios, supports separate settings for calls and multimedia.
• 🔊 Equalizer FX — in addition to amplifying the sound, allows you to fine-tune the equalizer to compensate for the shortcomings of the Mi speaker 9T (for example, to raise low frequencies).
• 📱 Precise Volume – gives access to “hidden” volume levels in Android that are not in the standard slider.

When using such applications, monitor the temperature of the smartphone. Constant operation at high volume can lead to overheating of the audio chip, especially when playing music with high frequencies.

Example of settings in Equalizer FX for Mi 9T:

1. Select the preset "Rock" or "Pop."
2. Increase the Pre-Amp slider to +3...+5 dB.
3. Raise the frequencies of 60-250 Hz by +4 dB for bass.
4. Reduce the 8-12 kHz frequencies by -2 dB to reduce distortion.

⚠️ Note: Some applications (e.g. Volume Booster) require permission to access the Notification Listener. Do not give it to unknown programs - this can be used to collect data.

5. Update or rollback of MIUI firmware

As mentioned earlier, the volume of the speaker on the Xiaomi Mi 9T may depend on the firmware version. Xiaomi periodically makes changes to audio drivers that affect sound.

• In MIUI 12.5, many users reported a decrease in volume due to optimisation of power consumption.
• MIUI 13.0.4.0 had a bug with a distortion of sound at volume above 70%.
• MIUI 14.0.2.0 partially fixed the problems, but added limits on the maximum volume.

To check if your problem is software-related:

1. Find out the current version of MIUI in Settings → About Phone → MIUI version.
2. Check out the reviews on forums (such as 4PDA or XDA Developers) about your version.
3. If the problem is massive, try to roll back to the previous stable version via Fastboot or MIUI bootloader.

For the kickback:

1. Download the required firmware version from the official Xiaomi website (Redmi K20 / Mi 9T section).
2. Unpack the archive and move the update.zip file to the root of the phone’s memory.
3. Go to Settings → About Phone → System Update, click on the three dots in the upper right corner and select Select a firmware file.

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Before rolling back the firmware, back up your data through Settings → Additional → Backup and Reset. rollback can result in loss of photos, contacts and messages.

6. Hardware causes of low volume

If the software methods did not help, the problem may lie in the hardware. on Xiaomi Mi 9T, the following malfunctions are most common:

• 🔈 Pollution speaker: dust and pile accumulate over time in the speaker grille, reducing its effectiveness. Clean the holes with a soft brush or compressed air (do not use sharp objects!).
• 🔧 Weakening of contacts: after falls or impacts, the plumes connecting the speaker to the motherboard may move away.
• 🔋 Wearing dynamics: over time, the dynamics lose elasticity, which leads to a decrease in volume. ~1500-2000 ₽).
• 🔌 Audio chip problems: Qualcomm WCD9340 (used in Mi 9T) It's sensitive to overheating, and if the sound goes away when you're under load, the chip might need to be soldered.

To diagnose a hardware malfunction:

1. Call the phone and press your ear against the speaker, and if you hear the sound from only one end, it's probably contaminated.
2. If the headphones are sounding normal, the problem is with the speaker or the connection.
3. Check the sound on the video, if the volume is normal and if it's silent, it's the software's fault.

If you suspect a hardware breakdown, you should contact a service center. Self-repair without experience can damage the motherboard or loss of warranty (if it is still valid).

Record the sound on the recorder and compare it with other devices|

Check the sound on the headphones |

Check the speaker grille for contamination |

Try to play the sound through a Bluetooth speaker|-->

7.Alternative solutions: Bluetooth and external devices

If you can not increase the volume of the built-in speaker, consider alternative ways:

• 🎧 Bluetooth headphones or speakers: modern models (e.g. Xiaomi Mi True Wireless Earbuds or other devices) JBL Go 3 will give a better sound than the built-in speaker.
• 🔊 FM-Transmitter: Devices like Nulaxy KM18 allow you to broadcast sound from a smartphone to car or home acoustics through FM-radio.
• 📱 Outside USB-C dynamics: some models (e.g, JBL SoundBoost 2) connect directly to the connector and operate without a battery.

For the Xiaomi Mi 9T, the Bluetooth 5.0 variant is particularly relevant, which supports the aptX codec for high-quality audio transmission.

1. Go to Settings → Connected Devices → Bluetooth Settings.
2. Select the connected device and activate the option Sound Quality (aptX).

If you listen to music or watch videos frequently, external acoustics will not only solve the volume problem, but also relieve the load from the internal speaker, prolonging its life.

FAQ: Frequent questions about volume increase on Xiaomi Mi 9T