SBC Bluetooth in smartphones and headphones Xiaomi: codec analysis, settings and alternatives

Have you ever noticed that the music in Xiaomi’s wireless headphones doesn’t sound as clear as it does through a wired connection? Or why the device specs always mention SBC Bluetooth support, but rarely explain what it means in practice? This codec is the basic standard for transmitting audio over Bluetooth, and it’s in every device of the brand, from the budget Redmi Buds to the flagship Xiaomi 14 Ultra.

In this article, we will discuss in detail what SBC is, why Xiaomi uses it by default, how it affects sound quality, and whether it can be replaced with more advanced codecs like aptX or LDAC. You will also learn how to check the current codec in your device and what settings will help improve the sound. Spoiler: in most cases, SBC is not a bottleneck - the problem lies in the wrong bitrate parameters or device compatibility.

What is SBC and why is it used by Xiaomi?

SBC (Subband Coding) is a mandatory audio codec for all devices with support for the A2DP (Advanced Audio Distribution Profile) profile, which was developed in the 1990s as a universal standard for transmitting compressed audio over Bluetooth. Unlike proprietary codecs like aptX (Qualcomm) or LDAC (Sony), SBC does not require royalties, making it an ideal choice for budget devices.

In Xiaomi devices, the SBC codec is used by default for several reasons:

• 🔹 Universal Compatibility: Works with all Bluetooth devices, even legacy ones.
• 🔹 Low power consumption: critical for headphones and smartphones with limited battery.
• 🔹 Minimum latency: Important for syncing audio with video (e.g. in Xiaomi Pad 6).
• 🔹 Lack of license fees: reduces the cost of devices.

But SBC has its drawbacks: It uses lossy compression, which can degrade sound quality at high bitrates, for example, when you stream music in FLAC format over SBC, some of the high-frequency parts are lost, but for most users, the difference is not critical — especially when compared to cheap speakers in budget headphones.

SBC vs AAC vs aptX: Comparison of codecs in Xiaomi devices

To understand how much SBC is inferior to alternative codecs, compare it with the most common variants supported in Xiaomi devices:

In practice, the difference between codecs is only noticeable when using high-quality headphones, for example, if you listen to music through Xiaomi Buds. 3T (who only support SBC and AAC), The transition to aptX will not give a tangible increase in quality due to the limitations of the speakers themselves. LDAC The difference will be obvious.

⚠️ Note: Some Xiaomi devices (such as Redmi Note 12) in the Bluetooth menu display supported codecs, but actually only use the codecs. SBC, If the headphones are not compatible with advanced standards, check this through the engineering menu!

How to Check Which Codec Is Used in Your Xiaomi

Many users are unaware that their smartphone or Xiaomi headphones support multiple codecs. To find out which one is active at the moment, follow the instructions:

1. Connect the headphones to the smartphone via Bluetooth.
2. Open Settings → About Phone → MIUI version and tap 7 times on the line “Kernel version” (activates the hidden developer menu).
3. Go back to the Settings → Additional → Developer settings.
4. Find the Bluetooth Audio Codec (could be called the Bluetooth Audio Codec).
5. Slip on it - the list of available codecs and the current active one will appear.

If you only have SBC on the list, it means that either your headphones don't support other codecs, or they're disabled at the firmware level. For example, Redmi Buds 4 Active only has SBC by default, AAC specs are listed.

For more detailed diagnostics, you can use applications like Bluetooth Codec Changer (requires root rights) or Developer Options Shortcut for quick access to settings.

Can you replace SBC with another codec in Xiaomi?

Technically, but with reservations: In most Xiaomi devices, the codec is automatically selected based on compatibility with the connected device, but there are ways to force it to change:

• 📱 Through the engineering menu: in MTK Engineering Mode (for MediaTek processors) or Qualcomm Service Mode (for Snapdragon) can be manually specified to the priority codec. X5 Pro path to be ##36446337## → Hardware Testing → Audio → Bluetooth Audio.
• 🔧 With help. ADB: Adb shell settings put global bluetooth_a2dp_codec_priority"aptX,LDAC,AAC,SBC" Preference order (required) USB-debugging).
• 🔄 Firmware update: in some cases (e.g. Xiaomi) 12S Ultra) adding support LDAC through OTA-update.

⚠️ Warning: Forced codec change to unsupported codec can cause communication interruptions or audio distortions, for example, if your headphones don't support aptX, but you force your smartphone to use it, the sound will be intermittent or disappear altogether.

For most users, the best option is to leave the SBC or AAC if the headphones do not support more advanced standards, except for audiophile models like the Xiaomi Buds 4 Pro, where LDAC really unlocks the potential of sound.

Optimizing sound through SBC: bitrate and buffer settings

Even if your Xiaomi device only uses SBC, the sound quality can be improved by adjusting the codec settings.

• 🎵 Bitrate: by default in SBC 224-328 kbps is used. The higher the value, the better the quality, but the higher the power consumption. K60) You can choose a fixed bitrate:
• 🕒 Buffer: increasing the size of the buffer (in ms) reduces the likelihood of sound breaks, but increases latency. Optimal value for music is 300-500 ms, for video - 100-200 ms.

These settings require access to ADB or root rights, and without them, you can try third-party applications like Bluetooth Auto Connect or SoundAssistant, which indirectly affect the parameters of audio transmission.

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If the sound is intermittent after changing the bitrate, reduce the value to 256 kbit / s or increase the buffer size to 400 ms. This is especially true for budget models like the Redmi A2, where the weak Bluetooth module.

It is important to understand that SBC does not support high sampling rates (maximum 48 kHz), so even at maximum bitrate you will not get a sound level of FLAC 96 kHz. However, for streaming music (Spotify, Apple Music) or podcasts will not be the difference.

Xiaomi SBC Problems and How to Solve Them

Despite its versatility, SBC can cause problems — especially in Xiaomi devices with custom firmware or outdated software.

If problems persist, check the Bluetooth version of the smartphone. For example, in the Xiaomi 11T Pro with Bluetooth 5.2, SBC problems are unlikely, and in older models like Redmi 9A (Bluetooth 5.0), they may manifest due to hardware limitations.

⚠️ Attention: In some firmware MIUI (Especially global versions) support for advanced codecs is artificially disabled. X3 Pro for the European region aptX may not appear in the list, although hardware is supported).

The future of SBC in Xiaomi devices: what to expect?

Despite the advent of more advanced codecs, SBC will remain the basic standard for Xiaomi for at least another 5-10 years.

• 🔄 Backwards Compatibility: Millions of Devices (from Redmi) 5 Xiaomi 13 Lite only supports SBC/AAC.
• 💰 Savings on licenses: aptX and LDAC Requires contributions from manufacturers.
• 📱 Optimizing for the mass market: 90% of users do not notice the difference SBC 328 kbit/s and AAC 256 kbps.

At the same time, flagship devices (such as the Xiaomi 15, expected in 2026) will expand support for LC3, a new codec from the Bluetooth LE Audio standard. It promises better quality at the same bitrate as the SBC, plus support for multithreaded audio (for example, to connect multiple headphones to the same smartphone at the same time).

The LC3 is already being tested in the Xiaomi Buds 5 (a model for the Chinese market), and it could replace the SBC in budget devices in the coming years.

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If you’re buying Xiaomi headphones in 2026, pay attention to LC3 support – a future standard that will eventually supplant SBC in the brand’s ecosystem.

FAQ: Frequent questions about SBC in Xiaomi