Sound quality issues in Xiaomi wireless headphones? Maybe it's the wrong Bluetooth codec. By default, smartphones often use outdated SBC, which limits bitrate and degrades sound. In this article, we'll discuss how to manually switch the codec to more advanced AAC, aptX or LDAC, depending on the formats your headphones support.
It’s important to understand that not all codecs are compatible with every Xiaomi model, for example, aptX requires support from the chipset, and LDAC is only available on flagships with Qualcomm Snapdragon 8xx. We’ll detail how to check compatibility, activate hidden settings, and avoid typical errors when changing the codec.
Why Change the Bluetooth Codec to Xiaomi
A codec is an audio compression algorithm that determines how sound is transmitted over Bluetooth.
- 🎧 Sound quality – bitrate, sampling frequency, support for Hi-Res Audio.
- 🔋 Latency – critical for games and video (e.g., aptX Low Latency reduces lag to 40ms).
- 📶 Communication stability – some codecs work better in jamming environments.
- ⚡ Battery consumption – complex codecs (for example, LDAC) They can put the battery down faster.
By default, MIUI and HyperOS choose SBC, a versatile but outdated codec with a bitrate of up to 328 kbit/s. For comparison, LDAC supports up to 990 kbit/s, and aptX Adaptive dynamically adjusts to communication conditions. If your headphones support advanced formats, changing the codec can radically improve the sound.
What Bluetooth codecs support your Xiaomi
The list of available codecs depends on the chipset and Bluetooth version in your smartphone. Below is a compatibility table for popular Xiaomi models:
| Xiaomi model | Chipset | Bluetooth | Supported codecs |
|---|---|---|---|
| Xiaomi 14 Ultra | Snapdragon 8 Gen 3 | 5.4 | SBC, AAC, aptX, aptX HD, aptX Adaptive, LDAC, LC3 |
| Redmi Note 13 Pro+ | Mediatek Dimensity 7200 Ultra | 5.3 | SBC, AAC, LDAC, LC3 |
| POCO F6 Pro | Snapdragon 8+ Gen 1 | 5.3 | SBC, AAC, aptX, aptX HD, LDAC |
| Xiaomi 12T | Dimensity 8100-Ultra | 5.3 | SBC, AAC, LDAC |
| Redmi 10C | Snapdragon 680 | 5.0 | SBC, AAC |
To find out which chipset is in your device, go to Settings → About Phone → All Specifications → Processor. If your model is not in the table, check the specifications on the official Xiaomi website or through the CPU-Z app.
⚠️ Note: Headphones must also support the selected codec. WH-1000XM5 work LDAC and AAC, a AirPods - only with AAC. Check the characteristics of your headset!
How to check the current Bluetooth codec on Xiaomi
Before you change the settings, make sure that the codec is the problem.
- Connect the headphones to your smartphone.
- Open Bluetooth Settings (Settings → Connections → Bluetooth).
- Click on the icon. ⚙️ near the name of your headphones.
- Scroll down to the section Additional settings or Sound Quality.
If there's no codec, it's hidden in the engineering menu, and to see it, you need to activate the developer mode.
Click 7 times on the MIUI version in Settings → About Phone |
Return to Settings → Additional → For Developers |
Turn on the Bluetooth | debugging switch
Reboot the phone.-->
After the reboot, the Bluetooth settings will have Codec or Sound Quality, and if it's not there, use the ADB method (described below).
Method 1: Change the codec through hidden MIUI/HyperOS settings
On most Xiaomi smartphones, you can change the codec without root rights, through the engineering menu.
- Open the phone app and enter the code: ##4636##
- In the menu that appears, select Phone Information.
- Scroll down to the Bluetooth block.
- Click on the Audio Codec and select the desired option from the list.
If #4636### is not working, try an alternative method:
- Install Bluetooth Codec Changer from Google Play (Android 10+ is required).
- Run it and give permissions to change system settings.
- Select connected headphones and an affordable codec.
⚠️ Note: HyperOS (the new firmware Xiaomi) may not have an engineering menu. ADB Apps like Developer Quick Settings to access hidden settings.
💡
If the sound starts to break after changing the codec, go back to SBC or AAC – your headphones may not support the format you choose.
Method 2: Change the codec through ADB (for advanced users)
If standard methods don’t work, you can force codecs to be set via Android Debug Bridge (ADB), which requires a computer and basic command line knowledge.
Steps:
- Download ADB Tools and unpack the archive.
- Turn on the smartphone debugging by USB (Settings → For developers).
- Connect your phone to your PC and in the command line (in the folder with adb.exe) do: adb devices (the name of your device should appear).
- Enter the command to view the current codec: adb shell settings get global bluetooth_a2dp_hw_codec_priority
- To install a new codec, use: adb shell settings put global bluetooth_a2dp_hw_codec_priority "AAC,SBC,aptX,LDAC" (List the codecs in order of priority, starting with the desired).
Example of commands for popular codecs:
- For aptX. HD: adb shell settings put global bluetooth_a2dp_hw_codec_priority "aptX-HD,aptX,AAC,SBC"
- For LDAC: adb shell settings put global bluetooth_a2dp_hw_codec_priority "LDAC,AAC,SBC"
⚠️ Attention: Wrong commands ADB Before experimenting, back up your settings via adb backup.
What if the ADB can’t see the device?
Solving problems after changing the codec
Sometimes, after a codec change, there are problems. Let's look at the typical cases and how to fix them:
| Problem. | Possible cause | Decision |
|---|---|---|
| The sound is interrupted or lost. | Incompatibility of codec with headphones | Return to SBC or AAC, update the firmware of headphones |
| High latency of sound | Used by LDAC or AAC with low bitrate | Switch to aptX Low Latency or LC3 |
| Poor sound quality | Bitrate is limited to Bluetooth settings | Enable high quality audio in headphone settings |
| Bluetooth shuts down on its own | Conflict with energy conservation | Add headphones to exclude battery optimization |
If the problems persist, try:
- 🔄 Reboot the phone and headphones.
- 📱 Reset Bluetooth settings (Settings) → Connections → Bluetooth → ⋮ → Reset the settings).
- 🔧 Update the firmware of the smartphone and headphones.
💡
On HyperOS, after changing the codec, you may need to reconnect the headphones again – remove them from the list of devices and pair from scratch.
The Best Bluetooth Codecs for Different Scripts
The choice of codec depends on your tasks:
- 🎵 Music (Hi-Res Audio): LDAC (990 kbps) or aptX Adaptive (up to 420 kbps) Suitable for Tidal, Apple Music Lossless.
- 🎮 Games and Videos: AptX Low Latency ~40 ms) or LC3 (Bluetooth 5.2+).
- 🏃 Sport/street: AAC (a) good stability; or SBC (maximum compatibility).
- 🔋 Battery savings: SBC or AAC (less processor load).
On Xiaomi smartphones with Snapdragon 8xx chipsets, the LDAC codec only works when the Sound Quality mode is turned on in Bluetooth settings. To do this, after selecting the codec, go to Settings → Sound → Bluetooth Sound Quality and select High Quality.
If you use Sony headphones (e.g. WH-1000XM4/XM5), you can manually prioritize your LDAC in their companion app (Sony Headphones Connect) and select a bitrate (44.1 kHz / 990 kbit / s for better quality).