Have you ever encountered a situation where the volume in a Bluetooth headphone or a Xiaomi speaker is acting strangely? It's too quiet, it's suddenly deafening, even though the sound slider on the smartphone hasn't changed? It could be the absolute volume feature of Bluetooth, the hidden Android setting that controls the volume synchronization between devices.
What is absolute volume and how does it work in MIUI and HyperOS firmware?
Why this feature can spoil the sound in Redmi Buds, Xiaomi Earbuds or Mi Portable Speaker speakers
How to turn on, disable or reset the absolute volume settings on Xiaomi, Redmi and POCO smartphones
Hidden nuances, which are not written even in official documentation.
What is Bluetooth’s absolute volume and why you need it?
Absolute Volume Bluetooth is a protocol that synchronizes the volume level between a connected audio device (headphone, speaker) and a sound source (smartphone, tablet). In theory, the function should simplify control: you adjust the volume on your phone, and the headphones automatically adjust to this level.
The feature appeared in Android 6.0 Marshmallow as part of the A2DP 1.3 standard (a profile for transmitting high-quality audio over Bluetooth).
- 📱 Firmware versions (MIUI 12/13/14 or hyperos).
- 🎧 Headphone/column models (e.g. Redmi Buds 4 Pro support it better than budget Mi Basic 2 models).
- 🔄 Implementing the protocol by the audio device manufacturer (some brands ignore absolute volume signals).
The main problem: at Xiaomi, absolute volume often doesn’t work correctly – especially on custom firmware or after updates. Users complain about volume spikes, the inability to make the sound quieter than a minimum threshold, or, conversely, the maximum level limit.
How absolute volume affects the sound in Xiaomi headphones
If the feature is active, the Xiaomi smartphone sends the audio device a command to set a specific volume level (in the range of 0-127 or 0-255, depending on the protocol).
| Script | Problem. | Reason. |
|---|---|---|
| Loudness jumps | When playing music, the sound level spontaneously changes. | Conflict between smartphone and headphone settings (for example, absolute volume is included in MIUI, and in headphones - its own adjustment) |
| You can't keep it quiet. | Minimum volume level too high | The headphone manufacturer has set a lower threshold (for example, Xiaomi Earbuds S does not lower the volume below 30%) |
| Maximum level limited | Even at full volume, the sound is quiet. | Absolute volume forcibly limits the upper limit (often found in HyperOS) |
The problems are particularly noticeable on devices with MIUI 14+ and HyperOS, where Xiaomi is actively optimizing Bluetooth power consumption. For example, in the Redmi Note 12 Pro+, absolute volume can be reset after reconnecting the headphones, and in the POCO F5, it can ignore commands when the battery is low.
⚠️ Note: If you are using headphones not from Xiaomi (for example, Sony) WH-1000XM5 or JBL Tune 510BT), Absolute volume can be unpredictable, and some brands block external volume commands, which makes the adjustment from the smartphone just not working.
How to check if the absolute volume is on on your Xiaomi
Unlike many Android features, Bluetooth’s absolute volume does not have a separate switch in settings.
Method 1: Developer (for experienced users)
Activate the Developer Mode:
- Go to Settings. → The phone.
- Tap 7 times on the MIUI version (or HyperOS build number).
- Back to Settings → Additionally. → For developers.
- Find the Bluetooth Debugging option or Bluetooth Absolute Volume (if not, the function is automatically controlled).
If there is an option, but its state does not coincide with the real behavior, then the firmware ignores the settings (often found on the POCO M6 Pro and Redmi 13C).
Method 2: Test with headphones
Connect Bluetooth headphones and follow the steps:
Change the volume on your smartphone|Listen, did the sound in the headphones change synchronously?|Turn off the headphones and plug in again.|Check if the volume level is still there.|Try adjusting the sound directly on the headphones (if there are buttons)-->
If the volume on the headphones changes only when adjusting on the device itself (not on the phone), the absolute volume is turned off or not supported.
How to turn off absolute volume on Xiaomi (3 working methods)
If the function interferes, it can be deactivated, and the methods vary depending on the firmware version and device model.
Method 1: Through ADB (Universal for all Xiaomi)
This method works on MIUI and HyperOS, but requires a computer to:
- Install ADB Tools on your PC.
- Connect your smartphone to your computer and allow debugging over USB.
- Open the command line and type: adb shell settings put global bluetooth_absolute_volume_enabled 0
- Reboot the phone.
To get it back, replace 0 with 1.
⚠️ Note: On some devices (e.g. Xiaomi) 13T) after turning off the absolute volume through ADB It may be synchronized with headphones. Xiaomi/AirDots. In this case, resetting Bluetooth settings will help (see Method). 3).
Method 2: Engineering menu (for advanced)
This method is suitable for devices on Qualcomm Snapdragon (for example, POCO X6 Pro or Redmi K70):
- Open the Phone app and dial ##36446337##.
- Go to Hardware Testing → Audio → Bluetooth Audio.
- Find the Absolute Volume option and turn it off.
⚠️ Caution: Unknown settings in the engineering menu may disrupt the Bluetooth module!
Method 3: Resetting Bluetooth settings
If previous methods have not worked, try:
- Go to Settings → Connections → Bluetooth.
- Slap the icon. ⚙️ near the connected headphones.
- Select Forget the device.
- Reboot your smartphone and reconnect the headphones.
This method often helps on Redmi Buds 3 Pro and Xiaomi FlipBuds Pro, where absolute volume gets stuck after a firmware update.
💡
If the sound in the headphones is quieter after turning off absolute volume, check the EQ settings in the Mi Music or Spotify app – they can automatically lower the volume at low frequencies.
Why Absolute Volume May Not Work Even After Shutdown
Sometimes users are faced with the fact that the function continues to affect the sound, despite all the manipulations.
- 🔄 Bluetooth cache: Accumulated data conflicts with new settings. Clear cache to Settings → Annexes → Systemic → Bluetooth.
- 📦 Headphone firmware: Outdated software in Redmi AirDots or Mi True Wireless can ignore smartphone commands. Check for updates in the Mi Home app.
- 🔧 Conflict with MIUI-Optimizations: In some versions of the firmware (for example, MIUI 14.0.4 for Xiaomi 12) absolute volume is controlled at the kernel level and is not turned off by standard methods.
- 🎛️ Hardware restrictions: Headphones with their own DSP (Digital audio processor can block external commands (for example, Xiaomi Buds 4 with a digital audio processor) ANC).
If nothing works, the last option is to roll back the firmware to an older version of MIUI, where the absolute volume worked correctly. For example, on the POCO X3 Pro, many users return from HyperOS to MIUI 13 precisely because of sound problems.
How to check the version of the headphone firmware?
Absolute volume in different Xiaomi models: compatibility table
Not all Xiaomi smartphones and headphones work at absolute volume in the same way, and the following are the most popular devices (based on user reviews and tests):
| The device | Support for absolute volume | Typical problems | Decision |
|---|---|---|---|
| Xiaomi 13/13 Pro (HyperOS) | Yes (on by default) | Volume jumps when switching tracks | Disconnection via ADB or Bluetooth reset |
| Redmi Note 12 Pro+ (MIUI 14) | Yes (partially) | It doesn't work with Redmi Buds 3 Lite | Update of the headphone firmware |
| POCO F5 (HyperOS) | Yes (maximum limit bugs) | You can't set the volume above 70%. | Manual adjustment of settings through the engineering menu |
| Xiaomi Pad 6 | No (ignores commands) | Volume is regulated only on headphones | Use third-party players (e.g. Poweramp) |
| Redmi Buds 4 Active | Yes (but with delays) | Loudness changes with delay | Turn off absolute volume on your smartphone |
If your model isn’t in the table, check the reviews on forums (like 4PDA or Mi Community). Often absolute volume issues are solved by updating the firmware or resetting to factory settings (but this is an extreme case!).
💡
On HyperOS devices, absolute volume is most often turned on by default and has no visual switch, and the only reliable way to turn it off is through ADB.