How to increase the volume of the speaker on Xiaomi Redmi Note 9 Pro: from standard settings to hidden features

Why the Redmi Note 9 Pro speakers sound quiet and what to do about it

Owners of the Xiaomi Redmi Note 9 Pro often face the problem of insufficient volume of the built-in speakers - especially when listening to music, watching videos or while calling. The manufacturer limits the maximum sound level for security reasons (risk of damaging the speakers) and compliance with EU standards.

The causes of low volume can range from software limitations of MIUI to physical wear and tear on speakers. In 80 percent of cases, the problem can be solved without repair, whether by settings, engineering menus or specialized applications. But it's important to understand that artificially raising volume above factory limits reduces the life of speakers and can lead to distortion of sound.

In this article, we will discuss 7 working volume-up methods on the Redmi Note 9 Pro, from the safest to the most advanced, root-rights-requiring methods. Each method is tested on current versions of MIUI (including MIUI 14 based on Android 12/13) and does not require disassembly of the device.

1. Standard MIUI settings: what can be squeezed without risks

Start with the basic settings - they won't hurt the speakers or void the warranty.The Redmi Note 9 Pro has a few hidden options that many users miss:

• 🔊 Sound amplifier in call settings: go to Settings → Sound. → Amplify the sound and activate the call option, which will increase the microphone volume and speaker during conversations by 15-20%.
• 🎵 equalizer MIUI: in the player or sound settings (Settings) → Sound. → Select the preset "Bas" or "Rock" - they automatically raise the total volume by 5-10 dB.
• 📱 For the street mode: in the same audio settings, turn on the option "Adaptive sound". The system will automatically raise the volume in noisy conditions (only works with headphones and Bluetooth devices).

If these options don’t work well, check to see if Do Not Disturb or Quiet Mode is activated in the notification curtain, and make sure that your app settings (such as YouTube or Spotify) don’t have a separate volume limit.

2. Engineering menu: hidden sound settings

The Engineering Mode allows you to bypass some of the limitations of MIUI, but it requires caution. Incorrect changes can damage the speakers or microphone. Before you start, write down the current parameters!

To open the menu:

1. Open the Phone app and enter the combination: ##36446337###
2. Select Hardware Testing → Audio → LoudSpeaker Mode.
3. In Max Vol, set the value 150 (default 100). Don't go above 160!
4. Save the settings and restart the phone.

Record the current parameter values

Do not change the microphone settings (section "Mic")

Do not raise the Max Vol above 160

Reboot your phone after the changes-->

⚠️ Attention: After changing the parameters in the engineering menu, the speakers may start wheezing at maximum volume. This is a sign of overload. Return the Max Vol value to 100-120 and use third-party applications to fine-tune.

3. Apps to amplify sound: top-5 tested utilities

If standard methods don't work, install one of the specialized applications. We tested 15 programs and selected the 5 most stable for the Redmi Note 9 Pro:

To install ViPER4Android (the most powerful tool) you will need:

1. Get root rights (instructions for Redmi Note 9 Pro – below).
2. Install Magisk Module "ViPER4Android FX".
3. In the application settings, activate Master Limiter and raise Pre-Amp to +3.0 dB.

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Before installing any sound booster, check it is compatible with your version of MIUI on the 4PDA forum.Some applications conflict with the shell and cause reboots.

4. Root rights: How to unlock full control of sound

Getting root permissions gives you access to the system files that control volume limits, and this is the riskiest method of doing this, which cancels the warranty and can lead to a device blinking if you make a mistake, but if you're ready to experiment, follow the instructions:

For Redmi Note 9 Pro (codename joyeuse), the method with unlocking the bootloader and installing Magisk is suitable:

1. Unlock the bootloader through the Mi Unlock Tool (requires a Mi Account binding and wait 7 days).
2. Install custom recovery TWRP for joyeuse.
3. Fly Magisk-v26.4.zip via TWRP.
4. Install the Audio Modification Library module to fine tune the sound.

After receiving root, you can edit /system/vendor/build.prop by adding the following lines:

ro.audio.loudness.enable=true


persist.audio.fluence.speaker=true




persist.audio.fluence.voicecall=true

⚠️ Warning: Incorrect editing build.prop can lead to a looped bootloop.Before changes, make a backup through TWRP. If the phone does not turn on after editing, restore the original file.

5. Hardware causes of quiet sound: when you need a workshop

If software methods didn't help, the problem could be physical damage to speakers or contacts.Typical hardware malfunctions of the Redmi Note 9 Pro:

• 🔧 Pollution speaker: dust and pile block the membrane. Clean the speaker hole with a soft brush or compressed air (do not use needles!).
• 💧 Moisture intake: Even after drying, the oxidized contacts turn down the volume.
• 🔊 Membrane detachment: when the membrane falls, the speaker can move away from the magnet. ₽).
• 🔌 Train problems: oxidation or breakage of contacts on the motherboard. Diagnosed by a multimeter.

Check the hardware serviceability of the speaker can be done using the test:

1. Open the engineering menu (#36446337##).
2. Select Hardware Testing → Audio → Speaker Test.
3. If the sound in the test is silent or absent, the problem is hardware.

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If the speaker wheezes or the sound disappears when you press the body, it's a 100% hardware malfunction. Software methods won't help here.

6.Alternative solutions: Bluetooth speakers and headphones

If you can't turn up the volume of the built-in speakers, consider the external devices. For the Redmi Note 9 Pro, you can:

• 🎧 Bluetooth headphones: AptX-enabled models (such as Xiaomi AirDots Pro 2) deliver cleaner sound than built-in speakers.
• 🔊 Portable speakers: even budget options (such as Xiaomi Mi Portable Speaker) sound louder and better.
• 🔌 USB-C audio adapters: allow wired headphones to be connected with an amplifier (for example, UGREEN USB-C to 3.5mm).

To connect Bluetooth devices:

1. Activate Bluetooth in the notification curtain.
2. Transfer the column/earphones to pairing mode (usually hold the power button for 3-5 seconds).
3. In the Bluetooth menu of the phone, select the device and confirm the connection.
4. In the audio settings (Settings → Connected devices), prioritize media playback.

If the Bluetooth sound is interrupted, update the speaker firmware and reset the settings (the instruction is usually in the user manual).

7. Frequent mistakes and how to avoid them

Redmi Note 9 Pro users often make mistakes when trying to turn up the volume.

• 🔊 Install boosters without compatibility check: some applications (e.g. Volume Booster) GOODEV) conflict MIUI 12+ They're rebooting. Always read the reviews. 4PDA.
• 🔧 Editing system files without backup: before changing build.prop or mixer_paths.xml Make a backup copy through TWRP.
• 📱 Ignoring updates: in new versions MIUI They often fix bugs with sound. Check the relevance of the software in Settings. → The phone. → Updating the system.
• 🔋 Volume up on discharged battery: at charge level below 20%, the system automatically lowers maximum volume.

If after experimenting with sound, the phone starts to overheat or discharge quickly, return all settings to factory settings (Settings → Additional → Resetting).

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No application can physically increase the power of the speakers, and all boosters are powered by software-based signal processing, which inevitably leads to quality loss or distortion.

FAQ: Answers to Frequent Questions