How to Make Sound Louder on Xiaomi Redmi 9: From Settings to Engineering Menu

Redmi smartphones traditionally offer great value for money, but owners of budget and mid-budget models such as the Redmi 9 often face insufficient volume of multimedia speakers, especially when watching videos in noisy places or while talking on speakerphone. Standard Android settings are sometimes not enough to break through the background noise of the street or traffic.

Fortunately, the MIUI operating system that powers the device’s shell provides users with advanced options for fine-tuning the audio stream. In this article, we’ll look at not only basic adjustments, but also hidden features that can dramatically increase sound pressure, and learn how to safely use the engineering menu, and which apps can actually help, and which only mimic work.

It is important to understand that software signal amplification has its own physical limitations, dictated by hardware. A speaker is a physical component with a certain maximum amplitude of membrane oscillations. Exceeding the permissible values can lead to distortions or even failure of the acoustic system, so all manipulations should be carried out carefully and consistently.

Basic setup of audio streams in MIUI

Before you take any drastic measures, you need to make sure that all the standard device settings are twisted to maximum and work correctly. In the MIUI shell, there is a division of volume into several independent channels: media, call, alarm and notifications. Often users forget that the slider, which is controlled by the volume buttons, depends on the context: if you do not run the video or music, you will change the volume of the call, not the multimedia.

For detailed control, go to Settings → Sound and Vibration. Not only can you set maximum slider values, but you can also activate Volume Up if available in your firmware version. You should also look at the equalizer built into the standard player or audio settings, where you can raise high frequencies for greater legibility.

Special attention should be paid to the setting of Dolby Atmos or Dirac Audio, if they are present in your version of the software. These technologies can both improve the quality and subjectively make the sound quieter due to the compression of dynamic range. Try to switch equalizer modes from "Normal" to "Clear" or "Bas" to assess the difference.

⚠️ Attention: When you activate Volume Up in the settings, the sound may become sharper and contain distortions at the maximum mark. Use this mode only when urgently needed.

Using an engineering menu to amplify the signal

One of the most effective ways to increase volume on the Xiaomi Redmi 9 is to edit the audio chip settings through an engineering menu that is designed for developers and service engineers, but is also available to ordinary users. Here you can change the gain (gain) for each stage of the speaker's operation, which gives a real volume gain that is not available through standard sliders.

To enter the engineering menu, open the Phone app and type the combination ##3646633##. If the code doesn't work, your firmware version may block direct access and you'll need to install a special assistant app, such as Engineer Mode MTK. After you log in, go to the Hardware Testing Audio → Audio → Audio Debugging tab.

In the list that opens, select Speech (for a conversational speaker) or Media (for multimedia). Next, select Normal Mode (normal mode) or Headset (for headphones). You will see a table with volume levels from 0 to 6. This is where the secret lies: the values in the Max Vol or Gain column can be increased.

Be very careful: setting too high a reading can overload the speaker, it is recommended to increase the readings in steps of 10-15 units, each time checking the result, remember the initial numbers before making changes, so that you can roll back in case of severe distortion or whistle.

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Before you change the parameters in the engineering menu, take a screenshot of the initial values of each volume level, which is the only reliable way to return everything to the same way if the experiment fails.

Third-party amplifiers

If you think it's too complicated or risky to tinker with an engineering menu, Google Play apps that are designed to amplify sound come to the rescue, and the way they work is to programmatically boost the signal before it's sent to a digital-to-analog converter, and among the many options, you can only pick out those that are highly rated and have been on the market for a long time.

Popular programs like the Volume Booster GOODEV or Super Volume Booster allow you to set the gain percentage, but it is worth noting that this is a digital zoom for sound: along with the useful signal, noise increases, and characteristic wheezing can also occur if the speakers can not physically cope with the load.

Importantly, these applications require permanent permissions to access the system and can consume additional battery power. Furthermore, after a system upgrade or device reboot, the gain settings can be reset, requiring re-activation. Use them only when the regular funds are really not enough.

⚠️ Attention: Prolonged use of 100% power amplifiers can cause the audio chip to overheat and rapidly wear the speaker membrane.

Configure Bluetooth devices and codecs

The problem of quiet sound on Redmi 9 can affect not only the built-in speaker, but also the connection over Bluetooth. If the wireless headphones or speakers seem quiet, the reason is often due to the dissynchronization of the volume of the phone and device, or in the selected data codec.

In Settings → Bluetooth, tap the gear icon next to the connected device. Make sure the volume sync switch is activated. This will allow you to adjust the overall sound level with buttons on the smartphone body, not just on the headset. In some cases, it helps to turn off and re-enable this feature.

For advanced users, a hidden section is available for developers. To activate it, you need to click on the version number 7 times in Settings → About the phone. Then, in the Developer menu, find the Bluetooth Audio Codec. Switching from the SBC codec to aptX or LDAC (if supported by both devices) can significantly improve not only the quality, but also the perceived volume of sound.

Analysis of causes of silent sound and table of decisions

Before applying software amplification methods, it is necessary to exclude physical and logical malfunctions. Quiet sound can be the result of contamination of the speaker grid, the presence of a protective film on the screen that blocks the sound channel, or software bugs after an update.

The table below shows the main scenarios and recommended actions for each case, which will help to systematize the approach to solving the problem and not waste time on inappropriate methods.

Also worth mentioning is the Noise Removal feature in call settings, which sometimes works too aggressively, cutting off not only background noise, but also a useful signal, making the person barely audible. Try turning off noise cancellation in the call menu to see if things change.

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Physical cleaning of the speaker mesh with a soft toothbrush often returns up to 30% of the lost volume that no program can add.

Cleaning speaker with ultrasound and maintenance

Over time, the Redmi 9 speaker grid accumulates dust, skin fat and pile, which creates a traffic jam and prevents the sound wave from coming out. Mechanical cleaning must be done very carefully so as not to damage the membrane. The use of sharp objects is strictly prohibited.

There's a software method of cleaning: play a video on YouTube that generates low-frequency sound (about 165 Hz) at maximum volume. Vibration created by the sound wave can knock some of the dust out of the dynamic head. Keep the phone down with the speaker during this procedure.

If the software cleaning didn't work, you can use a soft dry toothbrush. You can walk around the speaker grid in a light circular motion. You can also use a special sticky tape to collect dust from the surface, but don't glue it too hard to keep the safety net from coming off.

FAQ: Frequently Asked Questions