Xiaomi Redmi 9 is one of the most popular budget smartphones, but even experienced users sometimes have difficulties connecting wireless headphones. Unlike wired counterparts, Bluetooth devices require proper synchronization, customization of profiles and sometimes even firmware updates. In this article, we will analyze not only the basic connection algorithm, but also the nuances of working with different models of headphones (AirDots, Galaxy Buds, Sony WH-1000XM4, etc.), and also solve typical problems: communication interruptions, low sound quality or lack of the device in the list of available ones.
Redmi 9 has Bluetooth 5.0 support, which should theoretically provide a stable connection at a distance of up to 10 meters. However, in practice, users experience audio delays when watching videos, automatically turning off the headphones or forgetting them after rebooting the phone. We analyzed the causes of these problems and prepared checklists to fix them, if you just bought a new headphone or want to reconnect the old ones, this guide will help you get everything right the first time.
1. Preparation of the smartphone and headphones for connection
Before you connect devices, make sure both gadgets are ready to sync. The Redmi 9 should have Bluetooth enabled and the headphones in the search mode. Neglecting these steps is the main reason why the smartphone does not "see" the accessory.
First, check:
- 🔋 Headphone charge: Most models refuse to turn on when the battery level is below 5%. Connect them to the charger for 10-15 minutes if the indicator flashes red.
- 📱 Version. MIUI: Redmi 9 should be installed firmware not lower MIUI 12.Outdated versions may not support new Bluetooth protocols (e.g, LE Audio).
- 🔄 Resetting previous connections: if the headphones were already paired with another device, they need to "forget" on that gadget or reset the settings of the headphones themselves (usually holding the power button for 10-15 seconds).
Xiaomi AirDots headphones (and their clones) require confirmation on both devices when first connected – first on a smartphone, then on a second headphone (if it is a smartphone). TWS-Missing this step results in monosound or no communication.
Charge headphones to 30%|
Update MIUI to the latest version|
Remove headphones from the list of associated devices on other gadgets|
Enable the search mode on the headphones (usually holding the button 3-5 seconds) |
Shut down. VPN and energy saving modes on a smartphone-->
2. Step-by-step connection instruction
The pairing algorithm depends on the model of the headphones, but the general scheme looks like this:
- Open the Settings. → Bluetooth on Redmi 9 and activate the switch.
- Put your headphones in search mode: 🎧 For Xiaomi AirDots: Remove both headphones from the case and hold the touchpad on each for 3 seconds until the indicator starts flashing white/red. 🎧 For Sony. WH-1000XM4: Hold the power button for 7 seconds until you hear the voice message "Bluetooth pairing". 🎧 For Apple AirPods: Open the case cover and hold the button on the back for 5 seconds (the indicator blinks white).
In the list of available devices on your smartphone, find the name of your headphones (for example, Mi True Wireless Earphones or the name of your headphones). LE_WH-1000XM4) and tap him.
Confirm the pairing if a request appears (sometimes you need to enter) PIN-code - default 0000 or 1234).
When you successfully connect the headphones, you'll see the words "Connected." If you only hear the sound on one headphone. TWS-Remove both from the case and wait for automatic synchronization between them (indicators should burn the same way).
Xiaomi AirDots|Sony|Apple AirPods|Samsung Galaxy Buds|JBL|Others-->
3. Customize Bluetooth sound and profiles
By default, Redmi 9 uses A2DP (for music) and HSP/HFP (for calls), but for better sound quality, you can manually select codecs:
| Codec | Sound quality | Delay (MS) | Support for Redmi 9 |
|---|---|---|---|
| SBC | Mean (16-bit/44.1 kHz) | 100–200 | Yes (default) |
| AAC | High (24-bit/48 kHz) | 50–150 | Yes (must be included) |
| aptX | Very high (24-bit/48 kHz) | 40–80 | No (root requires) |
| LDAC | Maximum (32-bit/96 kHz) | 150–300 | Yes (with MIUI 12.5+) |
To change the codec:
- Put the headphones on.
- Open the Settings. → Bluetooth → ⚙️ (settings next to the headphone name) → Sound quality.
- Select AAC or LDAC (if available). LDAC is recommended for Sony WH-1000XM4, AAC is recommended for AirPods.
Bluetooth adapter will be required ROOT-access, because MIUI By default, it blocks the connection of external Bluetooth devices. You can find instructions for obtaining root rights for Redmi 9 in our separate article.