Modern smartphones Xiaomi often face the problem of poor cellular signal reception in buildings with thick walls or in remote areas. In such situations, technology Voice over Wi-Fi becomes a real lifesaver, allowing you to make calls over a wireless network, bypassing the operator's base stations. For owners of the popular model Redmi Note 8 This functionality is especially relevant, since the device supports the necessary communication standards, but often requires manual configuration.
Activating this feature not only improves voice quality but also saves battery power, since the phone doesn't have to constantly search for a cell tower signal in an area with poor coverage. However, despite the technology's support at the level gland, software shell MIUI The switch may be hidden or require specific actions to appear. In this article, we'll cover all the nuances, from standard settings to using hidden engineering menus.
It's worth noting that the success of this operation depends not only on your smartphone but also on your mobile operator's terms of service. Some providers require pre-activation of the service in your personal account, while others enable it by default. The VoWiFi service on the Redmi Note 8 only works if you have an active SIM card with 4G/LTE support, even if the call itself is made via Wi-Fi. Let's go through the setup process step by step, eliminating possible errors.
Checking the technology support by the operator and tariff
Before going into deep settings Android, you need to make sure that your mobile operator provides the service VoWiFi in your region. Even if your phone is perfectly configured, the feature won't work without network support. Major carriers often require you to replace your SIM card with a new one that supports 4G if you're using an older, years-old SIM card.
It's also important to check whether the service is blocked at the tariff level. Sometimes operators only enable this option for certain service packages or require separate activation via USSD request or an app. Ignoring this step is the most common reason why users waste time flashing their phones, even though the problem could be solved with a single call to support.
- 📱 Call your carrier's support team and check if the "Wi-Fi Calling" service is available for your number.
- 💳 Make sure your SIM card supports the 4G/LTE standard and is not older than 3-4 years.
- 🌍 Check your carrier's coverage map, as the service may not be available in some remote areas.
⚠️ Please note: Operators' personal account interfaces and tariff terms are updated regularly. Service availability may change, so always check your provider's official app for up-to-date information.
After receiving confirmation from your operator, you can proceed to setting up your smartphone. If the operator states that the service is connected, but Redmi Note 8 There is still no switch, which means the problem is with software limitations or regional firmware settings.
Basic network and SIM card setup in MIUI
The first step is to correctly configure the basic communication parameters in the menu of your Redmi Note 8It often happens that the function is hidden simply because the phone is operating in the preferred mode for using 2G/3G networks. To activate VoWiFi It is necessary to forcefully switch the network mode.
Go to Settings and find the section for SIM cards and mobile networks. Here, you need to select your primary SIM card and change the network type. Select the "Prefer 4G (LTE)" option. Without this step, modern voice protocols may not activate, as they rely on LTE data packages.
Next, make sure data is enabled in your mobile network settings. Even though the call is made over Wi-Fi, your phone must register with your carrier's network for authorization. If you see the "4G" or "LTE" icon next to the signal strength, the basic setup has been successful.
Now let's look at the Wi-Fi connection settings. Make sure you're connected to a stable network. If the router is far away or the signal is weak, your phone may not offer to switch to Wi-Fi Calling for fear of losing the connection during a call.
Finding the switch in the phone's standard menu
In most cases, if your carrier supports the service and the SIM card is configured correctly, the switch will appear automatically in the standard menu. MIUI The path may vary slightly depending on your Android version, but the logic remains the same. You need to find the "Wi-Fi Calling" section.
This option is usually found in the "Settings" -> "SIM cards and mobile networks" menu. Select the desired SIM card and check if there's a toggle switch. If so, simply turn it on. Once enabled, a handset icon or the word "Wi-Fi" may appear in the status bar next to the Wi-Fi signal strength.
If the option isn't available in the default menu, try searching through the settings. Tap the magnifying glass icon at the top of the settings screen and type "Wi-Fi" or "Calls." The system will automatically suggest the location of the required switch if it's available in the software for your firmware version.
☑️ Basic setup checklist
In some regions firmware Xiaomi This switch may be hidden. This often happens with global versions purchased from unauthorized importers, or with Chinese versions with global firmware installed. In this case, you won't be able to enable this feature using standard methods.
Using the engineering menu to activate
If standard methods fail to enable the feature, you can try the hidden engineering menu. This is a powerful diagnostic tool. Android, which allows you to manage hidden parameters of the radio module. For Redmi Note 8 There is a special code that opens access to testing functions.
Open the Phone app (dialer) and dial the combination ##869434##In some cases the code may differ, for example ##4636##, which opens the general testing menu. If the code entered is correct, the "VoWiFi Carrier Check" menu will appear on the screen.
##869434##In the menu that opens, you'll see a list of carriers. Find your carrier in the list. If there's a checkmark next to it or it says "Disabled," it means the carrier is disabling VoWiFi at the software level. Your task is to unblock it.
Tap your carrier's name to change its status to "Enabled" or "Allowed." Then, reboot your smartphone. This method doesn't work on all versions. MIUI, as Xiaomi often blocks access to these codes in security updates, but it's definitely worth a try.
⚠️ Caution: Be careful in the engineering menu. Changing unknown settings unrelated to VoWiFi may result in unstable operation of the communication module or complete loss of signal. Only change settings related to Wi-Fi Calling.
Setting up APN access points for VoWiFi
One of the technical reasons for the non-working function may be incorrect access point settings. APNIMS protocols responsible for voice transmission require these parameters to be configured correctly. If the APN settings are set to "empty" or the parameters are incorrect, the phone will not be able to register with the network for voice calls.
Go to SIM card and mobile network settings, select your SIM card, and go to "Access Point Names (APN)." Tap the menu (three dots or an arrow) and select "Reset to default settings." This is the safest way to restore the correct settings specified by your carrier.
If resetting doesn't help, you can try creating a new access point manually. You'll need to find the current APN settings for your carrier and network version (4G/LTE) on the provider's official website. Typically, you'll need to enter the name, APN, username, and password.
| Parameter | Meaning (example for MTS) | Meaning (example for Beeline) | Meaning (example for Megafon) |
|---|---|---|---|
| Name | MTS Internet | Beinternet | internet |
| APN | internet.mts.ru | internet.beeline.ru | internet |
| APN type | default,supl,ims | default,supl,ims | default,supl,ims |
| Protocol | IPv4/IPv6 | IPv4/IPv6 | IPv4/IPv6 |
Pay special attention to the "APN Type" field. It must be specified ims in the parameter list. This tag informs the system that this access point can be used for multimedia subsystems, including voice calls. Without this tag, VoWiFi will not work.
What should I do if my APN settings are not saved?
If you reset or don't save your settings after making them, you may have third-party optimization apps installed on your phone that are blocking changes to system files. Try disabling them or performing a reset in safe mode. The issue could also be related to superuser (root) rights, if you previously had them.
Troubleshooting firmware incompatibility issues
The most difficult situation arises when all the settings are correct, the operator confirms the service, but the switch still doesn't appear. This often indicates a firmware issue. Redmi Note 8 The configuration file (XML) for your specific carrier or region is missing. Xiaomi often cuts support for carriers from certain countries in global firmware releases.
In this case, the only solution is to change the region in your phone's settings or flash the firmware to a region officially supported by your carrier. For example, if you're in Russia but have a European firmware, switch the region in the "Advanced" -> "Region" settings to "Russia" or "Ukraine," where VoWiFi support is more widespread.
A more radical method is to install third-party configuration files through special applications or obtain root rights, which allows you to edit system files. carrier_configHowever, this method requires high skill and carries the risk of bricking the phone.
If you are unsure of your abilities, it is better to wait for a firmware update from the manufacturer. Engineers Xiaomi Support for new carriers is regularly added in security updates. Check for updates in the "About phone" menu.
Common mistakes and how to fix them
Even after successful activation, users may experience the VoWiFi icon appearing and disappearing, or calls being dropped. This may be due to aggressive power saving in MIUIThe system may "kill" background processes responsible for monitoring the Wi-Fi connection for calls.
Go to Battery settings and find the "Phone" or "System Services" app. Set the power saving mode to "Unlimited." This will allow the system to keep the data connection open, even when the screen is off.
Also, check if Airplane mode or Do Not Disturb mode is enabled, which can block incoming Wi-Fi calls. Sometimes, simply restarting the communication modules helps: turn on Airplane mode for 10 seconds, then turn it off.
If all else fails, there may be a problem with your router. Some older router models or specific NAT settings can block ports needed for voice traffic. Try connecting to a different Wi-Fi network (for example, via a hotspot on a different phone) to rule out a hardware issue.
Why is the VoWiFi icon lit, but calls don't go through?
This means that registration with the IMS network was successful, but the call itself is blocked. This could be due to insufficient internet speed (less than 1 Mbps), ports being blocked by your internet provider, or temporary issues on the carrier's end. Also, check if international calling is blocked if you're abroad.
Is it possible to use VoWiFi while roaming?
Yes, this is a great way to save money. While abroad, you can call numbers in your home country at your home network's rates if you're in a Wi-Fi zone. However, check with your carrier, as some charge the same rates for incoming Wi-Fi calls, while others charge free.
Does Wi-Fi quality affect call sound?
Absolutely. VoWiFi technology is sensitive to packet loss (jitter) and latency (ping). If the channel is busy (downloading a torrent or watching 4K video), the sound may become robotic or choppy. For comfortable calls, a speed of at least 1-2 Mbps is recommended.
Will VoWiFi work if my SIM card runs out of data?
Yes, voice calls over Wi-Fi typically don't consume your mobile data plan, as they use the Wi-Fi internet connection. However, initial network registration requires a minimum amount of data. If your account balance is empty and your internet connection is completely blocked, the call may fail.