“Volte sync enabled” on Xiaomi – what does it mean and how does it work?

You opened up the settings of Xiaomi and suddenly you saw a mysterious message: "VoLTE Synchronization is on"** What is this feature, why is it needed and why does the signal disappear after activation? If you ask these questions, you are not alone. VoLTE (Voice over) LTE) has long become the standard for modern networks, but its finer setup in firmware MIUI frequently cause confusion.

In this article, we will discuss in detail what is hidden behind the term “VoLTE synchronization”**, how this feature affects the quality of calls and Internet connections, as well as give step-by-step instructions for setting up for different models Xiaomi, Redmi and the Internet. POCO. Particular attention will be paid to typical problems - for example, when after turning on VoLTE mobile Internet stops working or calls are disrupted. You will learn how to check your carrier’s support for the technology, what settings to change in Engineer Mode, and why it’s sometimes best to turn off sync altogether.

If you encounter a “Volte failed to sync” error or just want to optimize your network, read on. We have collected up-to-date information for 2026, including data on compatibility with Russian operators (MTS, Beeline, Tele2, MegaFon) and nuances for firmware Global, China and other companies. EU.

What is VoLTE and why you need it synchronized on Xiaomi

VoLTE Technology (Voice over) LTE) Allows you to transmit voice traffic over networks 4G, Not to switch to outdated 2G/3G And that has three key benefits:

• 📞 Instant connection – the call is connected in 1-2 seconds (versus 5-10 seconds per phone) 3G).
• 🎧 Clear sound – bandwidth is 2-3 times higher than in traditional networks (codecs) HD Voice).
• 📶 Parallel operation of the Internet – you can simultaneously talk and use mobile data 3G Internet shuts down during a conversation).

However, for VoLTE to work correctly on Xiaomi, you need to synchronize settings between the smartphone and the operator’s network.

• 🔄 Updating the parameters IMS (IP Multimedia Subsystem – a protocol responsible for voice transmission over the Internet LTE.
• 📡 Adjusts the radio frequency to the local network requirements (for example, for Band 20 in Europe or Band 7 in Russia).
• 🔒 Verifies security certificates for encrypting calls (if the operator supports eSIM or VoWiFi).

Without synchronization, VoLTE can work unstable: calls will break, and the icon will be broken. 4G — It's not going to disappear during a conversation. MIUI (China Stable feature is enabled by default, but requires manual adjustment for Russian operators.

How to check if VoLTE sync is enabled on your Xiaomi

Before you configure VoLTE, make sure the feature is active. There are three ways to check:

1. Through the notification panel

During the call, look at the network icon in the status bar:

• 📶 4G/5G + tube icon - VoLTE works.
• 📶 3G/H+ — VoLTE is disabled (the call is on an outdated network).

On some models (for example, Xiaomi 13 Pro or XP) POCO F5) Next to the network icon may appear an inscription HD VoLTE.

2. In the settings SIM-map

Go to: Settings → SIM-maps and mobile networks → [choose SIM] → Enable VoLTE

If the option is active, but next to it there is the inscription "Synchronization is enabled"** - then the smartphone automatically adjusts the settings for the operator's network. If there is no option at all - your firmware does not support VoLTE (relevant to older models like the Redmi Note 5).

3. Through the engineering menu

For advanced users: enter the dialer code: ##4636###

Go to the Phone Information section and find the VoLTE provisioned line:

• 🔘 Yes, the synchronization was successful.
• 🔘 No – setup is required (see next section).

💡

If there is no VoLTE option in the engineering menu, upgrade the firmware to the latest version or install a patch for your model through the app. TWRP.

Step-by-step: how to enable and sync VoLTE on Xiaomi

If VoLTE is not working or sync is disabled, follow this instruction. MIUI.

Step 1. Check the operator's support

Not all Russian operators support VoLTE at all tariffs.Relevant data for 2026:

Step 2: Activate VoLTE in the settings

Go along the way: Settings → SIM-maps and mobile networks → [choose SIM] → Enable VoLTE

If there is no option, update the firmware or install MIUI version 12.5+ (For models older than 2020, some devices (e.g. Redmi Note 10 Pro) may need to enable developer mode and activate Force VoLTE option in the engineering menu.

Step 3. Synchronize your settings

If after activating VoLTE you see a notification “Synchronization enabled”**, but the calls do not work:

1. Reboot your smartphone.
2. Turn on and off flight mode (this resets the connection to the network).
3. Check what's in the Settings → Mobile network → Network type selected 4G (preferably).
4. If nothing helps, reset your network settings: Settings → System system → Reset → Resetting Wi-Fi, Mobile Network and Bluetooth.

Typical VoLTE Issues on Xiaomi and How to Solve Them

Even after you turn on sync, users often encounter errors, and let's take a look at the most common ones:

1. VoLTE is turned on but calls are disrupted or not connected

Causes and solutions:

• 📵 Weak signal. 4G — Check the signal level in the engineering menu (##4636##). If RSRP below -110 dBm, VoLTE won't work. Solution: go to a better coating location or turn off VoLTE.
• 🔄 Conflict with Dual SIM — on some models (Xiaomi) 12T, POCO X5) VoLTE only works on the main SIM. Solution: Change slots in places.
• 🔒 Operator-Blocked – Some tariffs (e.g. corporate) may restrict VoLTE.Solution: Call operator support and request activation.

2. After the inclusion of VoLTE, mobile Internet disappears

This is a typical problem for firmware. MIUI China. Solutions:

• 🌐 Reset APN — Go to Settings. → Mobile network → Access points (APN) and drop it to the factory.
• 📱 Disconnect sync – if the Internet is critically important than calls, turn off VoLTE in the settings SIM-map.
• 🔧 Manual setting IMS — Select from the Engineering Menu (#36446337##) IMS Settings → VoLTE → Enable and install IMS Registration = Registered.

3. Notice "Failed to synchronize VoLTE"**

An error occurs when:

• 📱 Smartphone is not certified for operation in the operator’s network (relevant for “gray” devices).
• 🔄 The firmware is modified (for example, installed Custom). ROM supportless IMS).
• 📡 Operator temporarily disables VoLTE support in your region.

Decisions:

⚠️ Note: If you are using a firmware MIUI China may not be able to sync VoLTE on a device purchased outside China due to regional restrictions, in which case flashing on Global or Google will help. EU version.

Hidden VoLTE settings: Engineer Mode and configuration files

If standard methods don't work, you can try manually setting up through the engineering menu. Attention: these actions require caution and are only suitable for advanced users.

1. Status check IMS

Enter the code ##4636##

Go to Phone Information and find:

• VoLTE provisioned - should be Yes.
• IMS Registration Status – must be registered.
• Volte Enable Flag – must be 1 (included).

If some parameters are displayed as No or 0, then the synchronization has not passed.

2. Forced Energization of VoLTE

For models on Qualcomm Snapdragon (most of them) Xiaomi/Redmi/POCO):

1. Enter the code ##36446337## (or #3644633## for older versions).
2. Choose. IMS Settings → VoLTE → Enable.
3. Install. IMS over LTE = Enabled.
4. In the section IMS Registration press Register.
5. Reboot your smartphone.

3. editing of the configuration file (for advanced)

On some firmware (e.g, MIUI 13 For the Redmi Note 11) VoLTE synchronization is blocked due to incorrect parameters in the file /system/etc/ims_config.xml. To fix this, root access and system file editor are required.

Instructions:

⚠️ Warning: Incorrect editing of system files can result in loss of communication or device "brick.

VoLTE vs VoWiFi: What’s the difference and what’s the best way to use it?

In addition to VoLTE, Xiaomi has another technology called VoWiFi (Voice over Wi-Fi), which allows you to call over Wi-Fi if you have a network. 4G It's not available:

When to use VoWiFi instead of VoLTE?

• 🏠 You are in a low-coverage area. 4G, But there's a stable Wi-Fi.
• 🌍 Traveling abroad (VoWiFi allows you to call at home rate).
• 🔋 You need to save battery power (Wi-Fi can be more energy efficient) 4G sometimes).

To enable VoWiFi on Xiaomi: Settings → SIM-maps and mobile networks → [choose SIM] → Enable VoWiFi

If there is no option, update the firmware or check the operator’s support.

💡

VoLTE provides better call quality in the coverage area 4G, VoWiFi saves where the mobile network is weak, and the best way to do this is to turn both functions on and let the smartphone automatically choose the best option.

Xiaomi models with better VoLTE support in 2026

Not all Xiaomi smartphones work equally well with VoLTE, and we tested popular models and ranked them for connection stability:

🥇 Top.-3 Support for VoLTE (without synchronization problems):

• 📱 Xiaomi 13/13 Pro - Full support VoLTE/VoWiFi, Automatic synchronization with Russian operators.
• 📱 Redmi Note 12 Pro+ 5G — stable operation even on firmware China (after manual settings).
• 📱 POCO F5 Pro – optimized for European and Russian networks, rare call breaks.

⚠️ Models with frequent synchronization problems:

• 📱 Redmi 10C — VoLTE only works on the slot. SIM1, requires manual activation IMS.
• 📱 Xiaomi 11T Pro - conflicts with Dual SIM, You may lose the internet when you call.
• 📱 POCO X3 Pro - on firmware below MIUI 13 VoLTE is unstable.

🚫 Models without VoLTE support (or with limited functionality):

• 📱 Redmi Note 8/8T — VoLTE only works on some Custom firmware ROM.
• 📱 Xiaomi Mi A2/A3 — Due to the “clean” Android there is no built-in support IMS.
• 📱 Smartphones until 2018 release – hardware limitations (no modem with VoLTE support).

If your model is on the list of problems, try:

1. Update the firmware to the latest version of MIUI.
2. Install Custom ROM VoLTE-enabled (e.g. Pixel Experience or LineageOS).
3. Use applications for Internet calls (e.g. Google Phone with VoIP support).

FAQ: Frequent questions about synchronizing VoLTE on Xiaomi