How to improve the sound quality of Bluetooth on Xiaomi smartphones

Modern Xiaomi smartphones have powerful processors and high-quality screens, but standard audio streaming settings often do not allow you to unlock the potential of even top-end headphones. Users often face a situation where the wireless headset sounds deaf, high frequencies are lost, and basses seem smeared. This is because the system defaults to choose the most compatible, but not the highest quality data transfer codec to ensure the stability of the connection.

To remedy this, you need to intervene with the Bluetooth stack of the MIUI or HyperOS operating system. In this guide, we will discuss how to activate advanced codecs, adjust the engineering menu and disable system constraints that stifle the audio stream.

Before you make any major changes, it's important to understand that sound quality depends not only on the phone, but also on the standards that the headset supports. If your headphones only support the basic SBC protocol, software improvements will have minimal effect. However, for devices that support aptX, aptX HD or LDAC, the next steps will be the key to studio sound.

Checking codec support and compatibility

The first step in optimization is to diagnose the current capabilities of your hardware. Xiaomi smartphones often hide the information about the available codecs in the depth of system settings, available only through the developer menu. Without activating this section, you will not be able to manage connection priorities.

To enter the advanced settings, you need to click on the build number several times in the About section. Once the corresponding notification appears, a new "Developers" item will appear in the menu, and this is where the key switches affecting audio codecs and transmission bitrates are located.

• 🎧 Find the Bluetooth Audio Codec and select the maximum available option from the list (e.g, LDAC or HD).
• 📡 Note Bit Depth and Select Frequency – Set the values of 24 bits/96 kHz if the headset supports.
• ⚙️ Make sure the “Switch off absolute volume” option is turned off so that volume control is synchronized between the phone and headphones.

⚠️ Attention: Forced inclusion of the codec LDAC On devices with a weak signal, it can cause music interruptions. If you notice a stutter, return the setting to automatic mode.

The system will try to connect through the chosen protocol, ignoring the less high-quality, but more stable options.

Activate hidden settings through the engineering menu

There's a deep system menu in the MIUI shells that's designed to test equipment by the plant's engineers, and through it you can access Bluetooth parameters that you can't see in the standard interface, and it's a powerful tool that needs to be careful.

To enter the engineering menu, you use a special code in the Phone app. Dial the combination ##6484## or ##3646633## (depending on the MediaTek or Qualcomm processor model).

MTK Engineering Mode -> Bluetooth -> BT Debug Mode

You can change the signal power and the receiver sensitivity, but the most useful feature for audiophiles is that you can view the connection logs, where you can see which codec was activated in real time.

• 🔍 In the Debug section, you can see the current bitrate of the connection in real time.
• 🔧 Some menu versions allow you to reset the cache of paired devices, which helps with problems with desynchronization.
• 📡 Check the value. RX Power to assess the quality of the received signal from headphones.

If you didn't find the explicit audio settings in this menu, don't despair. On Snapdragon processors, many settings are hidden and only accessible via the Snapdragon processor. ADB-The teams that will be discussed further.

Using ADB to deep tune Bluetooth

The most flexible way to manage audio streams on Xiaomi is to use the Android debugging bridge (ADB), which allows you to embed in the system tables and change values that are not available through the GUI. You will need a computer and a set of drivers installed.

First, connect your smartphone to your PC in USB debugging mode. Open the command line on your computer and enter a command to check the connection. Make sure the device is correctly identified before making changes to global settings.

adb shell settings get global bluetooth_codec_config

This command will show the current codec configuration code, so to force high-quality transmission, you can use commands to change priorities, for example, LDAC often requires you to set bitrate values.

• 💻 Execute the adb shell command to go to the device shell.
• 📝 Use the settings put global command bluetooth_codec_config 6 (The value may vary) for forced switching.
• 🔄 After entering commands, be sure to reboot the Bluetooth service or the entire phone.

⚠️ Attention: Incorrect teams ADB This can cause a cyclical reboot of the Bluetooth service. Always write down the initial values of the parameters before changing them so that you can roll back.

There are also ready-made ADB scripts that automatically apply optimal settings to different Xiaomi models, and they are safer to use manually if you are not sure about the command syntax.

Disconnection of system optimizations and energy saving

Aggressive energy saving policies in MIUI often stifle background processes, including audio processing.The system can limit the bandwidth of a Bluetooth module to save battery power, which directly affects the causality of the audio stream.

You need to find the "Bluetooth" app in your settings and change its settings. Go to Settings → Apps → All apps → Show system → Bluetooth. You need to disable all restrictions here.

From the energy saving menu, select No Limits mode, which will prevent the system from lowering the CPU frequency or turning off communication modules while music is playing, and you should also turn off the "Clear Memory" option for this process.

• 🔋 Set “No Limits” in the Energy Savings section for Bluetooth system.
• 🚫 Turn off Auto Start and Background Activity Restrictions if such items are available for system services.
• 📱 Make sure that Game Turbo does not activate the reduction in sound quality to save resources.

Another important aspect is turning off absolute volume, and sometimes dissynchronizing the volume levels of your phone and headphones leads to digital distortion, and try to switch that to the developer menu to find the optimal balance.

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If after turning off the optimizations, the battery began to discharge faster, try turning on the power saving mode only at night when the music is not playing.

Comparative table of Bluetooth codecs

Understanding the differences between compression formats will help you set up your device correctly. Not all codecs are equally useful for different genres of music. Some are better at conveying dynamics, others are better at detailing high frequencies.

Below is a table comparing the main characteristics of popular codecs available on Xiaomi devices. Note the maximum bitrate, as it directly affects the amount of information transmitted.

As you can see from the table, the difference between SBC and LDAC is huge. If your headset is high standards, but your phone uses SBC, you lose up to 70% of the quality of the original file.

Third-party applications and equalizers

Built-in audio customization tools are sometimes limited; third-party applications can take over audio stream management, offering more advanced processing algorithms and support for additional codecs, but they require Root rights for full functionality.

One of the most popular solutions is the Bluetooth Codec Changer app, which allows you to switch codecs without logging into the developer menu, and another powerful tool is Poweramp EQ, which can work bypass the system limitations of Xiaomi's equalizer.

Using third-party software also allows you to customize buffering, increasing the size of the buffer can eliminate cracking and interruptions in areas with poor reception, although this will add a small delay when watching videos.

• 📲 Install Bluetooth Codec Changer for quick profile switching.
• 🎚️ Use the Poweramp. EQ for fine-tuning the frequency.
• 🔌 Applications like Lesser AudioSwitch help force the sound to the desired output.

⚠️ Note: Installing applications requiring Root rights may disrupt warranty services and lead to blocking of some banking applications (Google Pay / Wallet).

If you do not want to get superuser rights, limit yourself to setting up the built-in equalizer, pre-selecting the preset “Linear” or “Flat” to avoid double processing of sound.

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Comprehensive approach: the combination of the right codec, power saving switch and high-quality sound source gives the maximum result.