Have you noticed that when you call Xiaomi Redmi 9, you hear too quiet, despite the maximum volume? The problem of low sound in the conversational speaker is one of the most common complaints of owners of this budget smartphone. The reasons can be rooted in both the software limitations of MIUI and the hardware features of the model. In this article, we will discuss 7 working ways to increase the volume, including hidden settings, engineering menus and secure modifications of the system.
It's important to understand that Redmi 9 has a single bottom speaker that handles both the media and the voice, which means that there are physical power limitations here, but they can be bypassed software. We're not going to offer dangerous methods like flashing or disassembling the phone -- just proven solutions that won't hurt the device. Let's start with the simplest and end with advanced tricks for power users.
1. Checking basic volume settings
Before you dig deeper, make sure that the problem is not in the trivial settings. On Xiaomi Redmi 9, the volume of the speaker is adjusted separately from the multimedia sound.
- 🔊 Press the up/down volume buttons during the call, and a slider with the pipe icon should appear on the screen.
- 📱 Go to Settings. → Sound and vibration → Volume and check if the settings for the "Call" mode are lost".
- 🔇 Make sure the phone does not activate Do Not Disturb or Quiet Mode (swipe down from the top edge of the screen).
- 🎧 If you use a headset, turn it off – sometimes the system “forgets” to switch back to the speaker.
Pay special attention to Settings → Special Features → Sound Amplification. You can turn on the "Enhanced Headphones" option, which indirectly affects the speaker, and experiment with sliders on this menu, sometimes even a small change has a noticeable effect.
⚠️ Warning: If the sound is completely lost after changing the settings, restart the phone. Redmi 9 sometimes triggers a bug with an audio driver, which is solved by the reboot.
Cleaning dynamics and checking for physical damage
A common cause of silent sound is contamination of the speaker — dust, pile, or even moisture can block the membrane. On Redmi 9, the speaker is located at the top of the phone (near the front camera).
- Turn off your phone and take a soft toothbrush (new or clean).
- Carefully, without pressing, walk along the speaker grille, removing visible particles.
- Use a compressed air can (to clean keyboards) to blow out the dust from the inside. Hold the balloon vertically at a distance of 5-7 cm.
- Check whether moisture has not hit the speaker before - the sign is white divorces under the bar or a distorted sound.
If the sound hasn't improved after cleaning, check the speaker for mechanical damage. On Redmi 9, a common problem is uncoupling the speaker membrane from the body, which leads to a significant loss of volume, in which case you will need to disassemble the phone and stick the membrane with a special glue (better contact the service).
3.Use of engineering menu to increase volume
All Xiaomi smartphones have a hidden engineering menu where you can manually increase the volume of the speaker.This method works on Redmi 9 with any version of MIUI, but requires caution - incorrect settings can lead to distortion of the sound.
Step instructions:
- Open the Phone app and enter the combination: ##36446337###
- You will be taken to the engineering menu. Go to the Hardware Testing → Audio → LoudSpeaker Mode section.
- In the Type field, select Sph (this is a conversational speaker).
- In the Value field, set the value from 140 to 160 (usually 128) by default. Don't put above 160 - risk of distortion!
- Press Set, then Save and restart the phone.
After the reboot, check the volume during the call. If the sound is louder but there are wheezing, reduce the value by 5-10 units. If there is no change, go back to the factory settings (value 128).
What to do if the engineering menu is not opened?
4.Tune audio through Samsung’s “SoundAssistant” app
It may sound strange, but Samsung's SoundAssistant app works great on the Xiaomi Redmi 9 and lets you fine-tune the volume. It doesn't require root rights and is safe for the system.
How to use:
- 📥 Download SoundAssistant from Google Play.
- 🔧 Open the app and give all the necessary permissions (access to the sound settings).
- 📈 Go to the Volume section by category and find the Calls item.
- 🔊 Increase the slider to the maximum (maybe even above the standard limit).
- 🔄 Enable the option of Separate Volume Adjustment so that the settings are not reset.
The app also allows you to adjust the amplification of the headphones and add vibration when calling. The main advantage is that the changes are applied immediately and do not require rebooting. MIUI settings may reset.
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If SoundAssistant is not installed, download APK from APKPure (select the latest version). Enable the "Installation from Unknown Sources" resolution in the security settings before installing.
5. Installation of a custom core or modified sound driver
For power users willing to take risks, there is a way to increase the volume through modified audio drivers, which requires unlocking the bootloader and installing custom recovery (such as TWRP), but gives the best result.
The most popular solutions for Redmi 9:
| Method | Need root? | Risk to the system | Efficiency |
|---|---|---|---|
| ViPER4Android | Yes. | Medium (may conflict with MIUI) | ⭐⭐⭐⭐ |
| Magisk + Audio Modification Library | Yes. | Low. | ⭐⭐⭐⭐⭐ |
| Castomic core (e.g., FrancoKernel) | Yes. | High (brick risk) | ⭐⭐⭐⭐⭐ |
| MOD-Firmware (e.g. Pixel Experience) | Yes. | High-pitched | ⭐⭐⭐ |
If you decide to do this, follow the instructions from the XDA-Developers forum for Redmi 9 (codenamed lancelot). Remember: any manipulation of system files deprives you of warranty and can lead to the failure of the phone.
⚠️ Note: Redmi 9 with firmware MIUI 12.5+ installation ViPER4Android It often leads to a reboot cycle. Before you experiment, back up through the TWRP!
Backup all the data.
Unlock the bootloader (bootloader)
Install TWRP Recovery
Download the compatible version of MOD-a
Check compatibility with the Android version-->
6. Alternative ways: from Bluetooth headset to external speakers
If the software methods didn't work, consider the hardware solutions, which won't turn up the volume of the built-in speaker, but will solve the audibility problem:
- 🎧 Bluetooth headset (for example, Xiaomi Mi True Wireless Earbuds) – the sound will be clear and loud, without reference to the speaker of the phone.
- 🔊 External speaker with 3.5 mm connector - connects through the adapter USB-C → Jack (Redmi 9 doesn't have a standard audio output).
- 📞 Speaker mode – during the call, press the speaker icon to switch to the main (multimedia) speaker.
- 📱 Sound amplification applications (e.g. Volume Booster or Equalizer) FX) — They work on top of the system settings.
For owners of Redmi 9, the last point is especially relevant: eQUALizer applications allow you to raise voice frequencies, making it more legible. Try using Equalizer FX to choose a preset "Voice" and increase the slider by 1-2 kHz - this will improve the audibility of the interlocutor.
7. When it is time to contact the service: signs of hardware malfunction
If none of the methods worked, the problem is likely hardware. Here are signs that the speaker on the Redmi 9 needs repair or replacement:
- 🔇 The sound has disappeared completely or has become intermittent.
- 🔊 There were severe wheezing or distortion even at minimum volume.
- 💧 The phone fell into the water or was exposed to high humidity.
- 🔧 The speaker cracks when pressing the body next to it (a sign of a peeled membrane).
- 📉 The volume changes itself during a conversation.
The cost of replacing the speaker with Redmi 9 in service centers is from 800 to 1,500 rubles (depending on the region). If the phone is warranty, do not try to repair it yourself - contact the official Xiaomi service. In case of self-repair, use only original spare parts (Dynamic article for Redmi 9 - MDY-007-14A).
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If the speaker started wheezing after the phone fell, it's likely that not only the speaker, but also the audio chip, is damaged, in which case repairs will cost more, up to 3,000 rubles.