Only one Xiaomi headphone works: why and what to do

A situation where a pair of Xiaomi or Redmi wireless headphones suddenly stop working one channel is familiar to many users. This can happen at the most inopportune moment: during an important call, during training or in the midst of a favorite movie. It is often early to panic, because in most cases the problem lies not in the physical damage to the speakers, but in the dissynchronization of the software part or contamination of contacts.

Bluetooth wireless audio technology requires a stable connection between both modules and the signal source. If one of the headphones is silent, this often indicates a failure in the TWS (True Wireless Stereo) synchronization protocol. The gadgets have simply forgotten each other and now work as two independent mono-devices, one of which could go into sleep mode.

Before you take the device to the service center or make a return, you should eliminate software errors. In this article, we will discuss in detail why only one Xiaomi headphone works, how to diagnose contacts and perform a complete reset of the headset to restore its normal operation.

The main reasons for dissynchronization TWS-headset

The root cause of silence in one channel is often a violation of the logical connection between the left and right modules. In True Wireless, one headphone (master) receives a signal from a smartphone and transmits it to the second (slave). If the headphone master can not “knock” to his partner, the sound will only go to him or disappear completely. This is a classic failure of the connection protocol.

Another common factor is the different battery levels: if one earphone is completely discharged and gone into deep sleep, and the second one is still charged, when removed from the case, they may not have time to sync before the smartphone system establishes a connection.

⚠️ Attention: Frequent use of headphones to the full discharge of one of the modules can lead to a deep discharge of the lithium-polymer battery, after which it will cease to take charge.

In places where a large number of wireless devices (offices, shopping centers) are congested, the signal may be lost, and one of the channels may “fall off” due to interference in the 2.4 GHz range.

Diagnosis of contacts and charging case

The most common, but common, reason is the lack of contact between the case chargers and the headphone, and if one of the modules didn't charge because the contacts were oxidized or the dust was disturbing, it just went out, and visually, it's not always noticeable, so a thorough inspection is required.

You need to look carefully at the bottom of the headphones and the inside of the case, and the contacts often accumulate earwax, pile from pockets or oxides, which creates an insulating film that prevents current from passing, and a cotton swab dipped in isopropyl alcohol or a special cleaning solution for electronics is ideal for cleaning.

The cleaning process should be delicate so as not to damage the spring-loaded contacts:

• 🧹 Gently wipe the gold contacts on the headphones themselves, removing visible plaque.
• 🔌 Blow the depressions in the charging case with compressed air or gently clean with a dry cotton swab.
• 🔋 Install headphones in your case and make sure the charge indicators catch fire (usually red or white).
• ⏳ Leave the device to charge at least 30-40 minutes, even if the lights were dim.

If the cleaning and the long charging hasn't changed, maybe the problem is in the case itself, and sometimes one of the charging legs inside the case fails, and it just doesn't put any voltage on one of the channels, and you can check this by plugging the case into the charging and moving the headphones inside -- if the indicator blinks, then the contact is bad.

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Use only dry wipes to wipe the case, and for contacts, a minimum amount of alcohol.

The procedure for complete reset (Hard Reset) headphones

If the hardware is good and the contacts are clean, but the sound is only going to one channel, you need to perform a software reset, which cleans the internal memory of the headphones from synchronization errors and makes them “get to know” each other again, this is the most effective method for Xiaomi Redmi Buds, AirDots and Mi True Wireless models.

Before you start resetting, it's critical to remove the old pairing. Go to your smartphone's Bluetooth settings, find your headphones in the list of devices, and click "Forget the device" or "Disable." Until the old record is deleted, the new reset may not work properly.

The reset process itself may vary depending on the model, but the overall algorithm for most Xiaomi headsets looks like this:

1. Place both headphones in the charging case.
2. Without closing the cover (if any), find the function button on the case or touch areas on the headphones themselves.
3. If the button is on the case: press it for 10-15 seconds before changing the color of the indicator (usually it flashes white or orange).
4. If there is no button on the case: simultaneously press the touch zones on both headphones (being in the case or outside it, depending on the instructions) for 20-30 seconds.

Once the lights flash to signal a reset, the headphones will go into pairing mode, you now need to turn on Bluetooth on your phone again, find the device in the list and perform pairing. It is important to connect one device (often called Redmi Buds or Mi True Wireless EB), not two separate channels.

⚠️ Note: During the reset procedure, do not remove the headphones from the case before the time, unless the instruction requires otherwise.

Smartphone settings and sound balance

Sometimes the problem is not the headset, but the settings of the smartphone operating system. Random user actions or OS updates can change the output parameters of the audio, first of all, it is worth checking the balance of channels that could shift completely to one side.

On Android smartphones, the path to settings is usually: Settings → Sound and Vibration → Balance. Make sure the slider is right in the middle. On iPhone, balance settings are in the Settings menu → Universal Access → Audiovisualization → Balance.

Also worth noting is the Mono-audio feature, which, if activated, sums up the sound from both channels and outputs to one speaker (or both, but without the stereo effect), which can be perceived as a malfunction of the second channel.

Another nuance is absolute volume. In some versions of Android, when you connect Bluetooth devices, the volume of the phone and headphones will be dissynchronized. Try the Developer Menu (which you need to activate by clicking 7 times on the build number in About Phone) to find the item "Disable Absolute Volume" and switch its state.

Specific models: Redmi Buds, AirDots and others

Xiaomi’s various wireless headphone lines have their own design and control features, which affect troubleshooting techniques. For example, early AirDots and Redmi Airdots lacked a reset button on the case, and had to use a complex combination of touches until the indicators flashed red and white.

In newer models like the Redmi Buds 3 Pro or Xiaomi Buds 3, control is done primarily through the Mi Wear app. If you don't have one headphone, the app can show its status as "Out of the grid" or "Low charge," even if it's in the case, which indicates that the case can't see the module.

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For current models with active noise cancellation (ANC), a single channel failure is often associated with overheating or software freeze of the noise maker module.

Owners of gaming versions such as Black Shark (a subsidiary brand) should check the low latency settings. The gamer mode requires more resources and energy, and with a weak signal, one channel can turn off to save charge.

When professional repairs are needed

Unfortunately, not all problems are solved by software. If neither reset, nor cleaning, nor reconnecting to other devices has helped, there is a high probability of hardware failure. Most often, the battery inside one of the headphones fails - it simply stops holding the charge or swells, losing contact with the board.

It can also cause mechanical damage to the dynamic membrane (for example, after falling or getting moisture) or oxidation of the main board inside the housing, which requires disassembly of the body, which is extremely difficult to do on your own due to the adhesive joint and the miniature size of the components.

Symptoms requiring access to the service:

• 🔇 The earpiece only makes a crackle or hiss, but not a voice/music.
• 🔋 The charge indicator on the problem headphone does not light up even after cleaning the contacts.
• 💧 The device was in water or exposed to high humidity.
• 📉 The volume of one channel is much lower than the other, even at maximum balance.

If the warranty is still valid, do not try to open the case yourself - this will lead to loss of warranty service.In the event of expiry of the warranty, repairs are often unprofitable due to the high cost of work relative to the price of new Redmi or Xiaomi. TWS-headphone.