Xiaomi Redmi 9 is one of the most popular budget smartphones, but many users face the problem of a quiet speaker, especially in noisy rooms or when using hands-free. In this article, we will discuss all possible ways to increase volume, from standard settings to engineering menus and firmware modifications.
It's important to understand that low volume can be related not only to software constraints, but also to hardware features such as speaker quality, grille dust or contact wear. Before you start radical methods, check the basic settings and physical condition of the device.
We analyzed feedback from Redmi 9 owners, lab-based sound tests and service center recommendations to get the fullest possible guide, all of which are distributed according to complexity, from simple to demanding technical skills.
1. Checking basic sound settings
Before you tamper with system files, make sure the problem isn't solved by standard means.There are a few hidden settings on the Redmi 9 that can affect the volume of the speaker.
Open the Settings → Sound and vibration and check:
- 🔊 Do Not Disturb – If activated, the sound of calls and notifications may be muted automatically.
- 📞 Call volume – a separate slider for a conversational speaker (not to be confused with multimedia volume!).
- 🔄 Adaptive sound – a function that automatically adjusts volume depending on ambient noise (may not work correctly).
- 🎧 Amplification of sound in headphones - sometimes affects the speaker (included in Settings) → Special facilities → Improvement of sound).
Also worth checking is Settings → Apps → App Management → Phone and resetting the settings for the standard call app. Sometimes, glitching in its work leads to a decrease in volume.
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If the speaker continues to work quietly after the call, reboot the smartphone - this will reset the time limits of sound that the system can impose after long conversations.
2. Cleaning of the speaker and checking of physical damage
On Redmi 9, the speaker is located at the top of the screen (near the front camera), and dust, hair, or moisture can block the sound waves, reducing the volume by 30-50%.
How to clean the speaker without indiscriminately:
- Use a soft toothbrush with a short pile - carefully run it through the speaker grille.
- Apply a can of compressed air (sold in electronics stores) - blow out the dust with short pulses.
- To remove moisture, place the phone in a silica gel bag (out of a shoe box) for 12 hours.
If the sound does not improve after cleaning, check the speaker for physical damage:
- 🔍 Examine the grate for dents or cracks.
- 🎵 Turn on the sound test through the engineering menu (instruction below) – if the speaker is wheezing or not making a sound at all, a replacement will be required.
- 🔌 Check the contacts of the speaker (when disassembling the phone) – oxidation or detachment of the plume can cause a quiet sound.
What to do if the speaker is wet?
3. Engineering menu: diagnostics and sound tuning
Xiaomi Redmi 9 has a hidden engineering menu (Engineer Mode), where you can test the speaker and change some of the audio settings. This menu is designed for service centers, but is available to ordinary users.
How to open the engineering menu:
- Open the Phone app.
- Enter the combination: ##4636###.
- Select the Hardware Testing option → Audio.
In the Audio menu you will see a few tests:
- 🔊 Normal Mode – Checking the main dynamics.
- 📞 Headset Mode - Headphone Test.
- 🎤 LoudSpeaker Mode – Handheld check (uses the main speaker).
- 🔄 Loopback - microphone test and speaker in the cycle.
To diagnose a speaker, select Normal Mode and listen to the test signal. If the sound is silent or distorted, the problem may be:
- 🛠️ Hardware malfunction of the speaker.
- 📱 Programmatic constraints MIUI.
- 🔌 Bad plume contact.
In some versions of the firmware, additional volume settings are available in the engineering menu.
- Go to Hardware Testing → Audio → Volume.
- Find Sip Voice Call or Voice Call settings.
- Try to increase the values (usually from 0 to 160).
⚠️ Warning: Changing the parameters in the engineering menu can damage the speaker at maximum volume!
Modification of system files (for advanced users)
If standard methods don't work, you can try changing the MIUI configuration files that control volume limits, which requires root rights or ADB.
Method 1: Editing mixer_paths.xml
This file contains the audio path settings in the system to change it:
- Install a file manager with root access (such as Root Explorer).
- Cross the path: /vendor/etc/mixer_paths.xml.
- Find the following lines: <path name="voice-call"> <ctl name="RX1 Digital Volume" value="84" /> <ctl name="RX2 Digital Volume" value="84" />
- Increase the value to 90-95 (no more!).
- Save the file and restart the phone.
Method 2: Use ADB (without root)
If you don’t have root permissions, you can try changing your settings using Android Debug Bridge (ADB):
- Install ADB Tools on your PC and connect Redmi 9 via USB (enable USB Debugging in the developer settings).
- Execute the command to check the current values: adb shell settings list | grep volume
- Increase the volume of the speaker with the command: adb shell settings put system volume_voice_call 10 (where 10 — significance 0 before 15).
⚠️ Warning: Incorrect editing of system files can result in loss of warranty or device blink.Before changes, back up the file mixer_paths.xml!
Backup data | Make sure root or ADB| Check battery power (minimum 50%) | Explore rollbacks on forums-->
5. Installation of custom firmware or core
If you haven't had any success with previous methods, a radical solution is to install custom firmware (like LineageOS or Pixel Experience), and many custom builds remove the volume limitations of MIUI.
The advantages of custom firmware for Redmi 9:
- 🔊 No artificial volume limits from Xiaomi.
- 🛠️ Ability to fine tune sound through Sound Mods.
- 📱 Optimized energy consumption and productivity.
How to install custom firmware:
- Unlock bootloader through the official Xiaomi website (requires an account binding Mi).
- Install TWRP Recovery (Castom Recovery)
- Download the appropriate firmware for Redmi 9 (codenamed Lancelot) from the XDA Developers forum.
- Sweat the firmware through TWRP, having previously made a backup.
Popular firmware to increase volume:
| Firmware | Features of sound | Complexity of installation | Reference |
|---|---|---|---|
| LineageOS 20 | No MIUI restrictions, ViPER4Android support | Medium | XDA |
| Pixel Experience | Pure Android with stock sound (often louder than MIUI) | Easy. | Official website |
| Havoc-OS | Advanced sound settings, support for Dolby Atmos | Difficult. | Havoc-OS |
⚠️ Attention: Installing custom firmware resets warranty and can lead to data loss.Before firmware check compatibility with the Redmi 9 model (codename lancelot)!
6. Hardware repair and speaker replacement
If all software methods have been tried and the sound is still quiet, the problem is probably hardware.
- 💥 Mechanical damage (shocks, falls).
- 🌊 Moisture intrusion (even if the phone hasn’t sunk, condensation can oxidize contacts).
- ⚡ Voltage surges (for example, when using non-original charges).
- ⏳ Natural wear (resource dynamics - about 3-5 years with intensive use).
The cost of replacing the speaker on Redmi 9 in service centers:
| Type of repair | Cost (rupe) | Repair time | Guarantee |
|---|---|---|---|
| Replacement of the Speaking Dynamic | 800–1 500 | 30-60 minutes | 3–6 months |
| Cleaning/repairing contacts | 500–1 000 | 20-40 minutes | 1-3 months |
| Diagnosis + replacement of the plume | 1 200–2 000 | 1-2 hours | 6 months |
If you decide to replace the speaker yourself, you will need:
- 🛠️ Set of screwdrivers (cross, flat, suction cup for the screen).
- 🔧 New speaker (original or analogue, for example, Xiaomi Lancelot Speaker).
- 🔥 A dryer or a glue heating station (Redmi 9 screen glued).
- 📱 Plastic blades for disassembly of the body.
Where to buy spare parts for Redmi 9?
Step-by-step instructions for replacement:
- Turn off the phone and remove it. SIM-map.
- Heat the screen edge with a hair dryer (~60°C) to soften the glue.
- Carefully tuck the screen with a plastic spatula, starting at the bottom edge.
- Disconnect the battery plume (to avoid short circuit!).
- Find the speaker (located at the top of the board) and unpold/unplug it.
- Install a new speaker and assemble the phone in reverse order.
⚠️ Warning: When disassembling the Redmi 9, it is easy to damage the screen plume or battery.If you have never repaired your phones, you should contact the service!
7. Alternative solutions: headphones and external speakers
If you can not increase the volume of the speaker, consider alternative ways:
1.Use of headphones with microphone
Even budget headphones (such as Xiaomi Basic or Redmi AirDots) will provide a clearer sound than the built-in speaker.
- 🎧 Best sound insulation in noisy places.
- 🔊 Adjustable volume without restrictions.
- 💰 Low price (from 500 rubles.).
2. Connecting an external speaker via Bluetooth
Portable speakers (e.g. Xiaomi Mi Portable Bluetooth Speaker) can be used as a speakerphone.
- Turn on Bluetooth on Redmi 9.
- Connect the column to Settings → Bluetooth.
- During the call, click on the speaker icon and select an external device.
3. Sound amplification applications
Some of the apps on Google Play promise to turn up the volume, but most of them are empty.
- 🔊 Volume Booster – Increases volume by 20–30% (requires root).
- 🎛️ ViPER4Android — Advanced equalizer (works on custom firmware).
- 📞 SoundAbout – Redirects the sound of calls to the main speaker (louder, but worse quality).
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Root-free audio amplification applications are often deceptions, either not working or making the sound quality wheezy, and the only reliable way is to edit system files or custom firmware.