Using a wireless headset makes listening to music and talking in a comfortable process without unnecessary wires, which is especially true for owners of popular smartphones Redmi series. However, the initial setup of the connection can raise questions for users who first switched to the MIUI platform or changed device. Owners of the Xiaomi Redmi 9 model often face the need to properly activate the search mode and provide a stable signal for high-quality sound.
The synchronization process in the Android operating system adapted to the MIUI 11 or 12 shell has its own nuances that differ from the standard protocol. Understanding these features will avoid common errors during the first run and ensure fast connection in the future. Below we will discuss in detail each step of the procedure, and also consider methods for eliminating possible failures in the communication module.
To get started, make sure your peripheral device is charged and ready to pair. This is a basic requirement, which often leads to the smartphone simply not seeing the accessory in the list of available gadgets. Next, we move on to step-by-step activation of the phone's functions.
Preparation of the device and accessories for work
Before you go to software settings, you need to physically prepare both devices for interaction. Many users forget that new headphones often come in transport mode to save battery power during storage. So the first step should always be to check the energy level in the headset battery.
If you use a full-size model or case inserts, make sure they are on. On most JBL, Sony or Xiaomi Mi True Wireless models, you need to press a special button on the case or hold the touch panels to activate the pairing mode. The indicator should start flashing blue or alternately blue and red, which signals search readiness.
On the Redmi 9 side, a number of pre-actions are also required: Make sure the screen is unlocked and you are on the desktop.This is necessary, as some Android security versions may restrict the background search of devices in order to save power.
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Keep your headphones and phone at a distance of no more than 1 meter from each other during the first connection attempt – this will eliminate the influence of external interference and speed up signal detection.
It’s also important to check if your audio device is connected to another gadget before, so if the headphones automatically connect to a tablet or laptop nearby, the Xiaomi phone may not see them, so temporarily turn off Bluetooth on other devices.
Activation of Bluetooth module in MIUI system
After the physical training, we move to the software part. In Xiaomi smartphones, wireless interface management is placed in the top of the quick access menu, which greatly speeds up the process, but for initial configuration and detailed management, you better use the main settings menu, where all the necessary parameters are available.
To open the control center, swipe down from the top right corner of the screen. In the curtain that opens, find a stylized "B" icon or a Bluetooth logo. Click on it to activate the module. If the icon is blue, the function is on and ready to go.
For a deeper setup, go to the main app menu and select Settings. In the list that opens, find the Bluetooth section, which is usually located at the top of the menu or in the Connections and Sharing category, which displays the current status of your device and a list of previously connected gadgets.
- 📱 Make sure the switch at the top of the screen is in the "On" position».
- 🔍 Check if your device is visible in the “Available Devices” list – it should show up with the model name.
- ⚙️ Click on the gear icon or arrow next to the headphone name for additional settings.
MIUI automatically starts scanning the ether as soon as the module is turned on. If the list is empty, pull the list down for a forced update. In some cases, it takes a few seconds for the device to appear on the list of available devices.
The process of pairing and pairing
When the module is activated and the headphones are switched to search mode, the most important step is to create a pair. Your Redmi 9 screen should show a list of available devices in the Bluetooth section. Find the name of your headset in it. It can match the brand or model, for example, Redmi Buds 3 or Galaxy Buds.
Click on the name of the device in the list. The system will start a handshake process, during which the encryption keys are exchanged. The screen may show a request for confirmation of pairing with the code or just a notification of connection. If the code is required, the standard value is often 0000 or 1234, but modern devices do not do this step.
When you successfully connect, you will hear a characteristic audio signal in the headphones, and on the phone screen the status will change to "Connected" or "Connected (music, phone)", which means that the audio and voice channel is fully activated.
☑️ Checklist of successful connection
Sometimes the system offers to install an additional app to control the headphones, especially if it is a third-party product. Only agree to install if you need specific features, such as setting up the equalizer or updating the firmware of the accessory itself.
Setting up profile and sound quality
After a successful connection, take your time to close the settings. Xiaomi allows you to flexibly adjust the settings of the connected device. To do this, in the list of Bluetooth devices, click on the gear icon or the arrow to the right of your headset name.
Here you'll see switches for different usage profiles. Media Sound, Phone Sound, and Contact Sync are usually available. Make sure all the items you need are activated. If you plan to use a headset only for gym music, you can turn off the contacts to speed up work.
Special attention should be paid to the settings of codecs if your Redmi 9 model and headphones support advanced compression formats. In the section Additional or Bluetooth Codecs (available from the engineering menu or through the developer), you can choose the priority codec. For high sound quality, AAC or aptX are preferable if they are supported by both devices.
| Parameter | Description | Recommendation |
|---|---|---|
| Media sound | Transmission of audio from players and video | Included. |
| Phone sound | Routing incoming calls | Included. |
| Contacts | Synchronization of the phone book | If you wish, |
| Absolute volume | Synchronization of phone volume and headphones | Included. |
Also available in this menu is the "Absolute Volume" feature, which, when turned on, will completely control the sound level in the headphones, ignoring their own adjustment, which is convenient because it eliminates the situation when the phone is at maximum volume and in the headphones quiet.
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Activation of the profile “phone Sound” is mandatory if you plan to answer calls through the headset, otherwise calls will come to the speaker of the smartphone.
Using the Developer Menu for Advanced Users
For those who want to gain maximum control over the audio stream, there is a hidden developer menu on Android, which is accessed on Xiaomi Redmi 9 by seven times clicking on the build number in the About Phone section. Once activated, a new option will appear in the main settings, "Extended Settings" or "Developers".
Inside this section, scroll down to the Network or Bluetooth block. Here you will find settings that affect connection stability and data quality. For example, the Bluetooth AVRCP version option allows you to select the playback control protocol. If the track switching buttons on the headphones are not working correctly, try changing the value from 1.4 to 1.5 or 1.6.
It also has the option to turn off absolute volume, which was discussed earlier, which could be useful for older headphone models that have their own volume control, which is not synchronized with the smartphone, in which case you will have to adjust the sound twice: on the headset case and on the phone screen.
⚠️ Warning: Changing the settings in the developer menu can cause the Bluetooth connection to work unstable.Write down the initial values before making changes so you can get everything back.
Another useful feature is Bluetooth Audio Codec, where you can force the transmission codec to choose, if you have Auto, the system will choose the best option, but if the sound is interrupted or of poor quality, manual selection of SBC (the most compatible) or AAC codec can solve the problem.
How to reset Bluetooth settings in the developer menu?
Solving Common Connection Problems
Even if you follow all the instructions, there can be situations when the device does not connect or does not work correctly. One of the common problems on Redmi 9 is overflowing the list of stored devices. If you have previously connected many gadgets, the phone may “forget” new ones or not see them due to the cache limit.
In this case, you need to clear the pairing list. Go to Bluetooth settings, click on the gear next to an unnecessary or old device, and select "Unpair" or "Forget the device." After deleting a few old profiles, try to find the headphones again.
Another common problem is desynchronization of audio and video, which often happens when high-quality codecs are used at the limit of communication range, the solution may be to approach the source of the signal or switch the codec to a lighter one, as described in the developer section.
- 🔄 Reboot your smartphone – this clears the temporary files of the communication module.
- 🔋 Check headphone charge – low charge often causes connection breaks.
- 📶 Turn off Wi-Fi at 2.4GHz – this range can interfere with Bluetooth.
If the headphones are visible but the connection breaks immediately after trying, try resetting the headset itself completely, usually by holding the power button for a long time or using a special combination of buttons (described in the instructions for a particular headphone model).
⚠️ Note: If the phone stops seeing any Bluetooth devices after the system update, the problem may be in the hardware module, in which case, independent methods will not help, and you will need a diagnosis in the service center.
Why do headphones wheez when talking?
Optimizing energy consumption and stability
MIUI is known for its aggressive energy saving policy, which can sometimes kill background processes associated with Bluetooth. To keep the headphones running consistently, especially when the screen is off, you need to add appropriate applications to the battery exceptions.
Go to Settings → Applications → All apps. Find your music player or messenger that calls through. Go to Saving Charge and select No Limits mode. This will prevent the system from turning off the background activity of the application, which will ensure a continuous stream of sound.
Also worth checking permissions. Make sure the player app has permission to work with Bluetooth devices and access to location (required for scanning in some versions of Android).
Regularly cleaning the Bluetooth cache also helps maintain connection speed, which can be done through the storage menu in the application settings by finding the system process “Bluetooth” (may require displaying system processes in the settings).