Modern wireless headphones from Xiaomi, Redmi and QCY often face the problem of out-of-synchronization, when sound is played in only one ear or channels work independently of each other. This is a classic situation that requires forced re-synchronization between left and right modules. Device owners often think that the gadget is faulty, but in most cases only the correct order of action is required when connecting.
In this guide, we will explore the technical details of how Bluetooth works in True Wireless Stereo (TWS) mode. Understanding how headphones find each other will help you avoid mistakes in the future.
The challenge is that once you've desynchronized, the headphones stop hearing each other and start to work as two independent mono devices, so you have to reset their internal pairing memory and re-create the pair, a process that's universal for most of the brand's models, from the budget Redmi Buds to the flagship Mi True Wireless.
Principle of work TWS-Systems and causes of desynchronization
True Wireless Stereo technology means that one of the ears (most often the right one) acts as a master receiving a signal from a smartphone, and the other as a client receiving data from a master. If this chain is broken, a dissynchron occurs, the cause may be the discharge of one of the modules below the critical level or simultaneous extraction from the case.
Often, users unconsciously knock the settings by connecting to the headphones from another device or not completing the process of turning off the Bluetooth menu. As a result, the internal memory buffer of the headphones is overflowing with old profiles, and they stop correctly transferring the audio stream between channels, this is especially true for models with active noise cancellation (ANC), where the load on the processor is higher.
It's important to understand that the wireless protocol is sensitive to interference, and if you're in an area with lots of Wi-Fi routers or other Bluetooth devices running, the signal may be interrupted, but if the problem is persistent and the sound is only on the left or right, it's the logic of the module pairing.
Technical details of the Bluetooth protocol
Complete reset of headphone settings before reconnecting
The first and most important step is to clear your connection history. You need to remove the device from your smartphone memory. Go to your Bluetooth settings, find your Xiaomi or Redmi, and click "Forget the device" or "Cancel pairing." This is a critical step that many people ignore.
After removal from the phone, you need to perform Hard Reset on the headphones themselves. For models with a touch button on the body (for example, AirDots), you need to pinch the touch panels on both headphones simultaneously for 20-30 seconds. Indicators should flash several times (usually red, then white), which signals a reset.
For models with physical buttons on the case (such as Mi True Wireless Earbuds Basic 2), the algorithm is different: Place the headphones in the charging case, open the lid, and press the reset button on the case case case. Hold it for about 10 seconds until the color of the indicator changes, which force the gadgets to search for a pair.
☑️ Complete reset algorithm
Correct algorithm of primary channel pairing
Once reset, the headphones go into standby mode. Now it's critical to follow the right sequence to create a stereo pair. Don't rush to turn on Bluetooth on your phone right away. The headphones must first find each other.
Take both of these headphones out of the case at the same time. For the first 3 to 5 seconds, they'll be actively looking for a partner to build an internal network, and you'll notice that the lights will flash at a high frequency, and only after one of the lights goes out or blinks slowly, and the other continues fast, can you assume that the stereo is created.
Now that the left and right channels are synchronized, you can activate a search on your smartphone. Only one name should appear on the list of available devices (for example, Redmi AirDots), not two identical ones. If you see two devices, then they are not connected again, and you need to repeat the reset procedure.
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If the lights are different colors (for example, one red, the other blue), this is a sure sign that the headphones are not synchronized with each other and work in monoregime.
Setup via Mi Home and Xiaomi Earbuds
For advanced configuration and battery status check, it is recommended to use proprietary software. For global versions of headphones, the Xiaomi Earbuds app (or Mi Buds) is often used, and for the smart home ecosystem, Mi Home. These utilities allow you to see the real state of charge of each module separately.
Inside the app, you can check the firmware version. Outdated software is often the cause of unstable connection. If the app suggests upgrading your headphones, be sure to connect them to charging and stable Wi-Fi before starting the process. The update reflashes the internal communication modules, eliminating logical errors.
The app menu also offers a gesture and noise reduction setting. If the sound is quieter after reconnecting one of the channels, check the balance in your smartphone's accessibility settings, as the headphone app rarely has a separate L/R balance slider.
Diagnostics of Sound and Connection Problems
If you have a problem after all the manipulations, you should do a hardware diagnostic, check the charging contacts on the headphones themselves and inside the case, if one of the modules is not charged due to the oxidation of the contacts, it will not turn on and will not be able to connect to the master.
Cleaning speaker grids can also solve the problem of quiet sound, which users mistakenly mistake for desynchronization: Use a soft brush or a special cleaning tape. The accumulation of sulfur can completely block the sound hole, creating the illusion of a breakdown.
The table below provides the main status indicators for popular models, which will help you understand where the device is:
| Status of the indicator | Meaning | Action. |
|---|---|---|
| Blinks white (quickly) | Search/pair mode | Search in Bluetooth. |
| Blinking white (slowly) | Connected/Waiting | Norma. |
| Burning red. | Low charge/charge | Put it in the case. |
| Blinks red and white | Resetting mode/Error | Repeat the reset |
Notice the behavior of the lights when you take them out. If one earbud doesn't light up at all, try to wipe the contacts with alcohol. Sometimes the oxide film interferes with the current, and the device stays dead until you clean the contacts.
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The lack of a reaction indicator on one of the headphones in 90% of cases indicates contamination of contacts, not a breakdown of the battery.
Specificity of connection to different operating systems
The connection process may vary slightly depending on the OS of your smartphone. On Android (especially the MIUI and HyperOS shells), the process is most smooth due to native integration. When you open a case next to an unlocked phone, the connection animation often pops up.
iPhone (iOS) owners should remember that pop-up animation may not appear if the headphones were previously paired with another Android device. In this case, you need to manually go to Bluetooth settings. Also on iOS, you sometimes need to confirm the connection by entering the code “0000”, although this is rare for Xiaomi.
On Windows or macOS computers, codecs can be difficult to use, and if there is sound but it is of poor quality or interrupted, try the device's properties to turn off Hands-free mode, leaving only Stereo, which will increase the bitrate of the audio being transmitted.
⚠️ Warning: Don't try to connect your headphones to a new device while they're active on the old one. TWS Often blocks reconnection if the master is busy transferring data to another device, even if the sound is not played back.
⚠️ Note: When you reset your headphone settings, all saved profiles will be deleted. If you used voice assistants or special equalizer settings, they will have to be reconfigured through the app.