Modern Xiaomi smartphones offer users a wide range of features that often go unnoticed in standard settings. One of these hidden but critical options is VoLTE, an acronym found in the top status bar of the device next to the network indicator. Many gadget owners see this icon, wondering about its purpose and the need for activation for everyday use.
LTE voice technology is dramatically changing the quality of voice communication, making conversations clearer and eliminating long pauses when connecting. In this article, we will explore what lies behind the mysterious name, why operators are actively implementing this standard, and how to properly configure your Redmi or Poco to work in high-speed mode without losing sound quality.
It’s worth noting that activating this feature depends not only on the capabilities of the smartphone itself, but also on the support of your mobile operator. Without support from the operator, activating the feature on the phone will not result in improved communication. Let’s figure out how to check compatibility and what steps you need to take to enjoy it. HD-sound.
Technological framework and working principle
Traditional cellular communication was based on second and third generation networks (2G and 3G), where voice was transmitted over dedicated channels with limited bandwidth. VoLTE (Voice over LTE) is a technology that allows voice traffic to be transmitted directly through a fourth generation LTE network using IP packet data. This means that your voice is digitized and transmitted as normal Internet traffic, but with priority in the packet queue.
The main advantage of this is that it's fast, and unlike a classic call, where the phone switches from 4G to 3G or 2G to start a conversation, there's no switching, and you stay in the coverage area of the high-speed network, which provides instant buzz and no delays in the beginning of the conversation.
Technical details of codecs
It is important to understand the difference between the regular Internet and the communication channel in this mode. Operators allocate a special priority channel (QoS - Quality of Service), thanks to which voice packets are not lost or delayed, even if you actively download files or watch high-resolution videos.
Key Benefits for Xiaomi Users
Owners of Xiaomi and Poco devices can experience a real difference immediately after activating the feature. The first and most noticeable advantage is the simultaneous operation of voice and mobile Internet. In the past, when an incoming call, the 4G network often switched to 3G, and the Internet connection was interrupted or slowed down greatly. Now you can talk and continue navigation, play online games or download files without interruptions.
The second important aspect is battery saving: Since a smartphone does not have to constantly switch the radio module between 4G and 3G/2G modes during a call, power consumption is reduced, especially for owners of models with a large screen size and capacious batteries, where every percentage of charge is counted.
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Use 5 seconds flight mode to reboot the communication module if the icon does not appear after the function is turned on, but the operator confirms support.
Sound quality is also taking a new level, with HD Voice technology, which works with LTE, transmitting a wider range of frequencies, and the voice becomes volumetric, and the metallic hue that is common in older networks disappears, allowing you to better distinguish between intonations and reduces fatigue during long conversations.
- 📶 Simultaneous work: Internet 4G Operates at full speed during a voice call.
- 🔋 Energy efficiency: Lack of constant switching between grid generations saves battery life.
- 🎙️ HD-sound: Crystal clear audio-conversation thanks to broadband codecs.
- ⚡ Connection speed: Instant communication without long waiting for horns.
Instructions for activating the function on MIUI and HyperOS
The process of enabling the technology may vary depending on the version of the MIUI operating system or the new HyperOS, and the region for which the smartphone is released. In most cases, if the SIM card and the operator support the standard, the settings are automatically set up when the card is installed in the slot. However, if the VoLTE icon does not appear, you need to check the settings manually.
Go to the settings menu of your device, find the connection and networking section, depending on the firmware version, it can be called «SIM-Maps and mobile networks" or simply "Mobile Networks" where you will need to select a SIM card for which you need to activate the service if there are two installed.
☑️ Verification of VoLTE activation
In the menu that opens, find a switch that says "Use VoLTE" or "Calls over LTE." Activate it. If it's not in the visible part of the menu, it may be hidden in additional settings or engineering menus, which we'll talk about below. Once turned on, reboot the device to apply the changes.
In some cases, especially on global versions of firmware for specific regions, the menu item can be hidden software, then activation is possible only through entering special codes into the engineering menu or through the application for hidden settings, but this requires caution.
| MIUI/HyperOS version | Location of settings | Standard heading of the paragraph |
|---|---|---|
| MIUI 12 / 13 | Settings → SIM- Maps and Mobile Networks | Use VoLTE |
| MIUI 14 | Settings → Mobile Networks → SIM Choice | Challenges through LTE |
| HyperOS 1.0 | Settings → Mobile network → SIM-card | VoLTE HD |
| Global ROM (Europe) | Often hidden or automatic | Depends on the operator. |
Solving problems with displaying the icon
Often, users are faced with a situation where the function seems to be enabled in the settings, but the cherished letter "H" or "D" in the circle next to the network divisions does not appear. This does not always mean a malfunction. First of all, make sure that you are in the zone of confident reception of the 4G signal. If the phone went to 3G or 2G mode due to a weak signal, the technology will not work.
The second common reason is the lack of service from the operator. Even if the phone supports the technology, without a plan that supports HD Voice or a similar name from your provider, the icon will not show up.
⚠️ Note: On some global versions of Xiaomi smartphones for markets where operators do not use VoLTE (e.g. some countries in Asia or Africa), the feature may be software-locked in firmware.
It is also worth checking if you have a custom firmware or modified_recovery_. Official global and Russian firmware usually contain all the necessary certificates. If you changed the software yourself, you may have deleted configuration files for specific operators.
Hidden settings and engineering menu
For advanced users who have a hidden power point from the manufacturer, activation via an engineering menu is possible, which requires you to enter special commands in the dialer. Be very careful, changing unknown parameters in this menu can lead to unstable operation of the communication module.
Try entering the code ##86583##. If the command is entered correctly, you should see a pop-up notification "VoLTE carrier check was disabled" (or enabled). This action removes the software lock of the operator's checkup, and the enable point may appear in the standard settings menu.
Other useful codes for diagnosis:
#4636## - Testing menu (Phone information)
#726633## - Shows VoLTE status (not on all models)In the testing menu (call code ##4636##) you can find the "Phone Information" section, which sometimes has a "VoLTE Provisioned" switch, which is activated by force to tell the networks that your device is ready to work in this mode, but this method does not work on all processors (Snapdragon or MediaTek) and Android versions.
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The use of engineering codes is effective only if the phone’s hardware and SIM card fully support the technology, and the lock is purely software.
Compatibility with communication operators
The success of the technology depends on the synergy of three components: smartphone, SIM card and operator equipment. In Russia and CIS countries, all major operators (the “big four”) have long supported this standard, however, in some cases, it is necessary to replace the old SIM card with a new one released after 2016-2017, since older chips may not have the necessary profiles.
Often, the activation of the service requires sending USSD-command or connect a free tariff option in the operator's application, for example, some providers have a service called "Calls through" LTE» or «HD-Without an active network-side service, the phone won’t initiate a connection over this protocol, even if all settings in Xiaomi are correct.
- 📱 Megaphone: Automatically for subscribers from 4G, check-in.
- 📱 MTS: Service "VoLTE", connection through a personal account or USSD.
- 📱 Beeline: Works by default on tariffs with 4G, You need support on your phone.
- 📱 Tele2: Activated automatically when a compatible device is available.
When roaming abroad, the technology may not work or be charged as a regular voice call rather than a packet of minutes.