Modern smartphones, especially the popular Xiaomi Redmi Note series, have a wide range of features that many users do not even know about. One of these hidden but extremely useful features is VoLTE (Voice over LTE), which radically changes the quality of voice communication, transferring it to the rails of high-speed 4G Internet. Many device owners notice the HD icon in the status bar, but do not understand its purpose or do not know how to activate this option if it is not on by default.
Redmi Note owners often face a situation where during a conversation the phone switches to 3G or even 2G, which causes the Internet to disappear or become extremely slow. VoLTE is designed to solve this problem, allowing you to talk and use mobile Internet at the same time. In this article, we will discuss in detail the way the technology works, its benefits for subscribers of operators of the “big three” and provide step-by-step instructions for activation through standard settings and engineering menus.
It is worth noting that the support of the feature depends not only on the firmware of your Xiaomi, but also on the tariff plan of the operator. Without the appropriate service from the provider, activating the settings in the phone will not give the desired result. SIM-The card supports voice transmission through the fourth generation network.
The principle of Voice over LTE technology
VoLTE is a standard for voice traffic over LTE networks, unlike traditional 2G and 3G networks, which used circuit switching. In the classic scenario, when incoming or outgoing calls, the smartphone forced to switch to lower frequencies (3G/2G), which took time and interrupted the data session. Xiaomi Redmi Note, which supports this standard, remains on the 4G network throughout the conversation.
The main difference is packet-based data, which is encoded into digital packets and transmitted in the same way as messenger messages, but with the highest priority in the operator's network, which provides crystal clear sound, devoid of the characteristic wheezing and noise characteristic of old networks. This process requires codec support. AMR-WB (Wideband, which greatly extends the frequency range of transmitted sound.
It is important to understand that using VoLTE consumes internet traffic, but generally operators do not charge these megabytes if you have the appropriate option or tariff connected. IMS (IP Multimedia Subsystem: If the tariff is provided, it is usually minimal, as voice data weighs slightly compared to video or music.
⚠️ Note: When using VoLTE in roaming abroad, additional Internet traffic charges may be charged, even if voice calls are formally free.Always check with your carrier before traveling.
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Check if your carrier supports VoLTE in your area.Even if the phone allows the feature to be enabled, in some remote areas, LTE coverage may be unstable, leading to a call disruption.
Key Benefits for Xiaomi Redmi Note Owners
Owners of Xiaomi devices get a number of tangible benefits when activating this feature. First, it is the simultaneous operation of voice and data. You can safely play online games, watch videos or navigate cards during a conversation without worrying about the drop in speed to EDGE. This is especially true for Redmi Note models, which are often used as basic working tools.
Second, it reduces the connection time significantly, dialing and horning almost instantly after you press the call button, 3G networks could have delayed a few seconds while the phone was looking for a free channel, and now the connection is established in 1-2 seconds thanks to IMS technology.
Third, energy efficiency improves, because the smartphone doesn’t have to switch between 4G and 3G/2G modes, which reduces the load on the modem and the processor. While the difference in autonomy isn’t always noticeable to the naked eye, in low signal conditions, the lack of constant reconnections helps Xiaomi to hold its charge longer.
- 🚀 Instant connection with the subscriber without long pauses before the beeps.
- 📶 Simultaneous voice and high-speed Internet 4G/5G.
- 🔊 HD-sound quality with extended frequency range.
- 🔋 More efficient battery consumption due to the absence of constant switching between communication standards.
How to check your operator’s support for VoLTE
Before you go into the settings of Xiaomi Redmi Note, you need to make sure that your mobile operator provides the service Voice over. LTE. In Russia, the main providers (MTS, Beeline, MegaFon, Tele2) They support this technology, but they require a number of conditions, and first of all, your data plan should include access to the networks. 4G.
Often, activation requires sending USSD-For example, some operators may have the default feature on new SIM cards, but old numbers require manual profile updates. It is also worth checking whether your device is registered on the operator’s network as VoLTE-enabled.
The list of supported devices is updated frequently. If your Redmi Note is not on the official list on the operator's website, this does not mean that the feature will not work. Global versions of MIUI firmware often have built-in certificates for working with most networks. However, if the phone is imported from China (CN Version), carrier profiles can be difficult to handle.
| Operator. | Need to connect the service | Tariffing of traffic | Features |
|---|---|---|---|
| MTS | Automatically on 4G tariffs | Not tariffed | IMS support is required in the profile |
| Megaphone | Activation is required (often free) | Not tariffed | Works in most regions of the Russian Federation |
| Beeline | Automatically. | Not tariffed | It is important to update the SIM profile |
| Tele2 | Automatically. | Not tariffed | Stable work in major cities |
⚠️ Note: If you have changed SIM-card to new card with saving number, VoLTE profile can be reset.
Activate VoLTE via the standard MIUI menu
In modern versions of the shell MIUI, When installed on the Xiaomi Redmi Note, the VoLTE switch is often hidden or displayed prominently, depending on the region of the firmware. First, try to find the option in the standard interface. Go to Settings, then select SIM-maps and mobile networks.
Select the SIM card you want if there are two. Look for a item called "Use VoLTE" or "Calls over LTE." If it's there and active (not grey), just turn it on. Once you reboot your smartphone, an HD or VoLTE icon should appear in the status bar.
If the switch is not available, it may mean that the operator is not added to the Xiaomi whitelist for your region, in which case it will not work with standard methods to enable the function, but there are ways to get around this restriction through the engineering menu or special codes, which will be discussed below.
☑️ Checking settings
Including through the engineering menu and codes
If the standard path didn't work, you can use the Xiaomi Engineering Menu, a powerful diagnostic tool that allows you to manage hidden modem parameters. To log in, type in the Phone app code ##4636##. If the menu opens, select Phone Information.
In the list that opens, look for "VoLTE Provisioned" or "Turn on VoLTE." Activate the switch. If the HD icon appears after that, the problem is solved. However, on newer versions of Android and MIUI, developers often block access to this menu through code.
In this case, the Activity Launcher app or special scripts help. You can also try the code ##86583##, which forcibly includes VoLTE Carrier Check. Once you enter, the message "VoLTE Carrier check was disabled" should appear, which means unlocking the function for all operators.
Codes for activating VoLTE on Xiaomi:
1. ##4636## (Engineering menu)
2. #86583## (Removal of operator lock)
3. ##86854## (Alternative verification code)What do I do if the codes don't work?
Possible problems and ways to solve them
Even after the feature is turned on, it can be difficult. Often users complain that the HD icon appears, but calls still break down in 3G. This may be due to the fact that 4G coverage is unstable in your location, and the phone automatically switches to a more reliable standard where VoLTE is not supported.
Another common problem is two-way communication. VoLTE only works if both subscribers are in 4G coverage and their phones support the technology. If you call an old button phone or smartphone without LTE support, the conversation will go through normal channels, but the quality on your side will remain high until the switching time.
Also worth mentioning is the conflict with Wi-Fi Calling. Some Xiaomi Redmi Note models don't know how to keep both types of calls active at the same time. If you have both modes on, Wi-Fi can be given priority, even if the cellular signal is excellent. Try turning off Wi-Fi calls in the settings to check the stability of VoLTE.
- 📉 Unstable signal 4G This leads to constant switching to 3G.
- 📞 The interviewer uses the device without support LTE or is in an uncovered area 4G.
- ⚙️ Settings conflict between VoLTE and Wi-Fi Calling in Android.
- 🚫 Operator has blocked service at the network level, despite phone settings.
⚠️ Note: It is not recommended to force the network mode "Only" LTE" (LTE Only) through the engineering menu for continuous use. In this mode, you may lose the ability to receive incoming inboxes. SMS Calls from emergency services because the phone will no longer see the network 2G/3G.
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The stability of VoLTE depends on three factors: operator support, the quality of 4G coverage in your area, and the right smartphone settings.