Modern smartphones like the Xiaomi Redmi 9C offer a wide range of telecommunications capabilities, among which VoLTE technology occupies a special place. It allows voice calls over fourth-generation networks, providing high sound quality and fast connection. However, users often face situations where this feature creates more problems than conveniences, from increased battery consumption to the inability to make a call in areas of unstable coverage.
Disable VoLTE on Redmi device 9C It may be necessary if your operator does not support the technology correctly or if you are often in places where you are not able to use the technology. 4G-The signal is weak and the phone is not switching to 3G In such cases, the device is forced to switch to operating mode only with 2G/3G It is important to understand that the management of this feature on Xiaomi smartphones can be hidden in different menu sections depending on the firmware version. MIUI.
In this article, we will discuss in detail all available methods of deactivating high-speed voice communication. We will look at standard menu settings, hidden engineering codes and specific features of working with SIM cards of different operators.
Understanding VoLTE technology and the reasons for its disabling
Voice over LTE technology is a voice traffic transmission through 4G packet data, bypassing traditional 2G and 3G channels. For a Redmi 9C owner, this means that during a conversation, the network indicator does not drop to "H+" or "E", but remains in "4G" mode. This allows you to simultaneously talk and use fast Internet, which is convenient for navigation or instant messengers during a call.
However, the implementation of this feature depends not only on the smartphone, but also on the infrastructure of the carrier. If the cell tower is overloaded or the 4G coverage in your area is unstable, the phone may try to hold the LTE connection for voice, which leads to a distortion of the sound or a complete communication breakdown.
Another common reason is compatibility. SIM-Old SIM cards issued several years ago may not work properly with new communication protocols, even if the tariff plan supports the new protocol. 4G. Xiaomi users also note that the active VoLTE feature sometimes conflicts with the power saving mode, preventing the screen from going out or preventing the device from sleeping deeply.
⚠️ Note: Before changing your network settings, make sure you have an alternative way to communicate, as in rare cases, resetting network settings may temporarily result in loss of mobile internet access before the device restarts.
It’s also worth mentioning that some carriers impose this service, and it can activate automatically after updating the MIUI firmware. Understanding how switching between networks works gives you complete control over your smartphone’s communication capabilities.
Standard method of disabling through the settings menu
The easiest and safest way to manage the high-speed communication function is to use the regular menu of the Android operating system with a shell. MIUI. In most cases, the manufacturer leaves this option available to the user, although the location of the switch may vary. 9C.
Open the Settings app and find the section SIM-This is where all the data and voice settings are concentrated. Choose the SIM card you want to change if you have two modules installed on the device. MIUI (12, 13 or 14, but logic remains the same.
Inside the settings menu SIM-Search for a card item called "Use VoLTE" or Calls by LTE. If the switch is active (blue or green), just click on it to deactivate the function"HD" or "VoLTE", which indicates a successful switching.
- 📱 Open Settings on the main screen.
- 📡 Go to section. SIM-maps and mobile networks.
- 🔢 Select the desired SIM card (SIM 1 SIM 2).
- 🔘 Find and turn off the switchboard "Use VoLTE".
If the icon remains after these actions or the function is turned on again after the restart, it is possible that the settings are applied by the operator remotely, in this case, you should check for system updates or contact your carrier’s support service to clarify the status of the service on the tariff.
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If the VoLTE switch is not on the menu, try to remove it. SIM-map, reboot phone, paste card back and check settings again – sometimes this updates network profile.
Use of the Engineering Menu for Advanced Settings
In situations where the standard switch is hidden by the operator or manufacturer, the Android engineering menu comes to the rescue. It is a hidden part of the system, designed for testing equipment, but also accessible to ordinary users. On Xiaomi Redmi 9C, it is logged in through a special set of commands in the call app.
Open the Phone app and dial ##4636##. If the code is entered correctly, the menu will open automatically, you don't need to press the call button. You will be met by a list of test modes; select Phone Information. This displays detailed signal and network management statistics.
In the list that opens, look for "Enable VoLTE provisioning." Unchecking this box forcibly disables modem-level support for the technology. Be careful: the interface may be in English, so focus on these terms. Changes take effect instantly.
##4636##It's worth noting that some versions of MIUI firmware may have this menu blocked, so if nothing happens when you type code, you've restricted your debugging access, and in this case, you've got to install a third-party app to access the engineering menu, but that requires a deeper knowledge.
⚠️ Note: In the engineering menu, do not change other settings, such as "Preferred network type", unless you are sure of their value. 2G) It could completely disconnect you.
☑️ Check before entering the engineering menu
Comparison of network modes on Redmi 9C
Understanding the differences between network modes helps you choose the optimal configuration for your environment. Redmi 9C supports several communication standards, and switching between them affects not only voice quality, but also Internet speed. Below is a table comparing the main characteristics.
| Parameter | 4G LTE (with VoLTE) | 3G / HSPA+ | 2G / EDGE |
|---|---|---|---|
| Sound quality | High (HD) | Average. | Low. |
| Connection speed | Instant. | 2-5 seconds | 5-10 seconds |
| Battery consumption | High on bad signal | Medium. | Low. |
| Simultaneous Internet | Available. | Depends on the operator. | Slowed or unavailable |
As you can see from the table, turning off VoLTE puts the device in a mode where the stability of the coverage, not the maximum speed, is the priority. 4G They're dense, and the difference may not be noticeable, but in the countryside or in buildings with thick walls. 3G-The signal is often more “breakthrough” and reliable for voice communication.
Also, it’s worth considering that some old plans don’t include voice over LTE. In this case, the phone will try to set up a VoLTE session, fail and only then switch to 3G, which creates a noticeable delay before the beeps.Forced shutdown of VoLTE eliminates this delay, as the phone immediately looks for a 3G network to call.
Network mode choices also affect navigation applications, and if you use your phone as a navigator in your car while you're talking, having active VoLTE is critical for real-time data, and if you use offline maps, switching to 3G while you're talking is not uncomfortable.
The influence of the operator and SIM-card
Remember that Xiaomi Redmi 9C is just a tool, and the quality of communication is determined by the operator. The largest providers (MTS, Beeline, MegaFon, Tele2 and others) have different requirements for support for VoLTE. Often it happens that the feature works perfectly on one SIM card and causes failures in another, even in the same place.
Operators can block or impose VoLTE use via remote commands, and if you change carriers but you leave your old SIM card, it may not be updated to work with the new protocols. SIM-new card with support 4G/UICC Often solves the problem without the need for deep phone setup.
- 📶 Check your operator’s coverage area in a specific area.
- 💳 Make sure yours is yours. SIM-card 4G (usually written on the map itself).
- 📞 Contact the operator to activate the VoLTE service at the tariff (if required).
- 🔄 Try to move SIM cards in slots if there are two of them.
There is also the term "IMS registration." If you see that the IMS is not registered in the network status, then the phone cannot establish a secure voice connection over LTE. In this case, disabling VoLTE is a logical step, since the function cannot technically work correctly.
What is IMS and why is it important?
Additional methods and resetting network settings
If none of the above methods worked, or if VoLTE is unstable (it turns on and off itself), it is recommended to reset the network settings. This action will return all connection parameters to factory values, removing possible software conflicts.
To do this, go to Settings → Connection and Sharing (or Additional Features) → Reset Wi-Fi, mobile networks and Bluetooth. Click Reset. Importantly, this action will delete saved passwords from Wi-Fi and associated Bluetooth devices, but will not affect your personal files, photos or contacts.
Once reset, the phone will reboot and you will have to re-enter wireless passwords, but often this "shaking" of the modem software helps to correctly determine the capabilities of the SIM card and disable unnecessary features such as VoLTE if they are not supported by the infrastructure.
⚠️ Note: After resetting the network settings, the phone may take some time (until then). 10-15 Do not panic if the connection does not appear instantly - let the system complete the configuration process.
In extreme cases, when software methods are powerless, users resort to installing third-party apps from Google Play that create a shortcut to a hidden settings menu. However, on current versions of Android (10 and above), on which Redmi 9C is based, the effectiveness of such applications is reduced due to system security limitations.
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Network reset is a safe and effective procedure that solves 90% of software problems with connecting and switching between 2G/3G/4G.