VoLTE on Xiaomi Mi9: how to disable the function and what will happen after

VoLTE (Voice over LTE) technology allows you to call over a 4G network, promising clearer sound and faster connection. However, on the Xiaomi Mi9, the flagship of 2019 with a Snapdragon 855 processor, this feature sometimes fails: it loses sound, calls are interrupted or the battery goes down quickly. If you encounter similar problems or just want to return classic calls on 2G/3G, our guide will help you completely deactivate VoLTE without losing the basic functions of the phone.

It is important to understand that disabling VoLTE does not amount to abandoning the 4G-You'll still be using high-speed mobile Internet, but calls will be going through traditional networks, like on old phones. Mi9 (including models with global and Chinese firmware, and explain which settings can block changes and how to get around them.

Why VoLTE can get in the way: real problems of Mi9 users

In forums and reviews, owners of Xiaomi Mi9 often complain about specific bugs associated with VoLTE.

• 📞 Call interruptions 10 to 30 seconds after connection (especially when switching between towers).
• 🔋 Accelerated battery discharge – up to 15-20% per hour in standby mode due to constant scanning LTE-network.
• 🔊 Sound distortions: echo, intermittent speech, or complete absence of the interlocutor’s voice.
• 📶 Roaming problems – VoLTE is simply not supported in some countries, but the phone is struggling to connect.

The reason for many of these problems lies in the imperfect implementation of VoLTE in firmware. MIUI 10-12 for Mi9. Even after updates, bugs may persist due to Qualcomm modems and carrier policies, such as MegaFon and Tele2 in some regions force VoLTE to be activated at the level of the operator. SIM-maps, which makes it difficult to disable.

Method 1: Disable VoLTE via standard MIUI settings

The easiest method is to use built-in system options, which is suitable for most MIUI versions (from 10 to 14), but may vary depending on the regional firmware.

Instructions:

1. Open the Settings app (cog icon).
2. Go to section. SIM-maps and mobile networks.
3. Choose yours. SIM-card (if two of them).
4. Slip on the network type or network settings item.
5. Find the VoLTE option (may be called 4G Calls or Improved Calls) and move the slider to the Off position.
6. Restart your phone to apply the changes.

If the VoLTE item is not on the menu, it could mean:

• 📱 Your firmware. MIUI modified (e.g. custom or regional version without VoLTE support).
• 📡 The operator has blocked the possibility of disconnection at the level SIM-Cards (relevant to Beeline in some rates).
• 🔧 The function is hidden in the engineering menu (see the following method).

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If after the VoLTE shutdown mobile Internet disappeared, check if the settings are not lost APN. To do this, go to the Settings. → SIM-map → Access points (APN) Choose your operator profile.

Method 2: Engineering menu – for advanced users

If VoLTE does not turn off through standard settings, you can use the Engineering Mode, which requires caution, since incorrect changes can disrupt the modem.

Step-by-step:

1. Open the Phone app and type the combination: ##4636## Some firmware may run an alternative code: #86583###
2. In the menu that opens, select Phone Information (or Phone Information).
3. Scroll down to the Set preferred network type block.
4. Choose LTE/WCDMA/GSM auto (PRL) or 3G/2G auto (without mentioning VoLTE).
5. Go back and find VoLTE provisioned – change the value to Disabled.
6. Reset the device.

⚠️ Note: On some versions MIUI for Mi9 The engineering menu can be blocked. If nothing happens after you enter the code, try using the app. MTK Engineering Mode (available on the Play Market), but note that it is designed for devices on Mediatek and Mi9 It's running on Snapdragon, so you'd better move on to the next one.

If the engineering menu is not available, an alternative way is to use the ADB-For this, for this:

1. Activate Developer Mode (7 times tap the MIUI version in Settings → About Phone).
2. Enable USB debugging in the developer settings.
3. Connect your phone to your PC and execute the command: adb shell settings put global volte_enabled 0

Method 3: Disconnection through USSD-operator

Some Russian operators allow you to control VoLTE through special USSD-This is the most reliable method, because changes are made at the level of the application. SIM-map.

If USSD-team didn't work:

• 📞 Call the operator and ask to disable VoLTE manually (clarify that we are talking about voice calls over the phone). 4G).
• 🔄 Try to remove and insert again SIM-map – sometimes it resets the network settings.
• 📲 Check if the video calling service is activated or HD-voice in the operator's personal office.

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USSD-The most common method is the team, as it works regardless of the version. MIUI. However, the operator can return the VoLTE settings after the tariff update or replacement. SIM-map.

What to do if VoLTE does not turn off: radical measures

If none of the above methods work, there are two options:

1. Network Settings Reset: Go to Settings → System → Settings Reset → Network Settings Reset. This will delete all stored Wi-Fi networks and mobile connection settings, but often helps reset forced VoLTE activation.
2. Install custom firmware: Firmware based on LineageOS or Pixel Experience for Mi9 (codename cepheus allows you to fully control the modem settings, but this requires unlocking the bootloader and can take away the warranty. OTG-In addition, banking applications (Sberbank, Tinkoff) can block work on uncertified builds.

Before you resort to radical measures, check:

• 🔄 Has the firmware been updated? MIUI Recently – sometimes after the update, VoLTE is automatically turned on.
• 📱 Is the second not used? SIM-Active VoLTE card (disable the function for both cards).
• 🛠️ Are there third-party network management applications (e.g. Network Signal Guru) that may conflict with settings.

Consequences of VoLTE shutdown: what will change

Many users are afraid to turn off VoLTE for fear of losing quality connectivity.

Xiaomi. Mi9 Disabling VoLTE most often leads to improved battery life (10-15% on user tests) and communication stability in areas with unstable conditions. 4G-But in megacities with good coverage. LTE-You may notice a deterioration in voice quality, especially if the other person is using VoLTE.

⚠️ Note: On some carrier rates (e.g., “All for communication” from MTS), disabling VoLTE may result in the loss of free minutes or other bonuses.

Alternatives to VoLTE: how to call clearly without 4G

If you have disabled VoLTE but want to maintain high quality communication, consider these options:

• 📞 Wi-Fi Calling (Wi-Fi Calling): Available in MIUI for most operators. Included in Settings → SIM-map → Wi-Fi calls require a stable internet connection.
• 💬 Voice Call Messengers: WhatsApp, Telegram or Viber offer high-quality voice over the Internet, often surpassing VoLTE.
• 📡 3G-codec-phone AMR-WB: Some operators (e.g. MegaFon) support improved voice quality in networks 3G. Check with support to see if this option is activated.

For Xiaomi Mi9 is especially relevant Wi-Fi Calling, as the phone supports this feature at the hardware level. The main advantage is that calls will take place even in the absence of a mobile network, if you have access to Wi-Fi.

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If you notice that calls are interrupted more often after you turn off VoLTE, try manually selecting a 3G network in the settings. To do this, install 3G Only (WCDMA) in the Network Type.

FAQ: Frequent questions about disabling VoLTE on Mi9