How to increase the speed of the Internet on Xiaomi Redmi 9: from basic settings to hidden chips MIUI

The slow internet on Xiaomi Redmi 9 is a problem that even new device owners face, and the reasons can be both in the hardware limitations of a smartphone (for example, the Wi-Fi 5 module instead of Wi-Fi 6) and in the software settings of MIUI, which are not optimized by default for maximum performance. In this article, we will discuss all possible ways to speed up mobile Internet and Wi-Fi, from simple changes to the settings menu to little-known tricks with engineering menus and alternative firmware.

The feature of Redmi 9 (codenamed lancelot) is the low-end MediaTek Helio G80 processor, which, when it is high, can artificially limit data transfer speeds. This also applies to network operations: if background applications are running simultaneously, Internet speed can drop by 20-40%. But don't be quick to blame the iron: 80% of the time, the problem is solved software.

Before you start settings, check the baseline speed through services like Speedtest or FAST.com. Write down the results, which will be useful for comparison after optimization. If the speed on Wi-Fi and mobile networks differ radically (for example, 100 Mbit / s vs 10 Mbit / s), first focus on the weaker channel.

1. Optimization of mobile Internet settings (4G/5G)

Redmi 9 can default to a traffic saving mode or an outdated communication standard. Here's how to fix it:

Go to Settings. → SIM-maps and mobile networks → [Yours. SIM-map] → Network type. Here, it's important to choose the most accessible standard:

• 📶 4G (LTE) — If VoLTE is available, include it separately in the same menu.
• 🌐 5G — If your carrier supports this standard in your city (on Redmi 9) 5G No, but for other models it is important).
• ⚠️ 3G/2G — Never choose these modes unless you are in a poor-covered area. 4G.

If the speed has not increased after the network type change, check APN-settings. Wrong parameters. APN They can limit speeds to 5 to 10 Mbps even if you have a good signal. APN:

1. Go to Settings. → SIM-maps and mobile networks → [Yours. SIM] → Access points (APN).
2. Click on the three dots in the top right corner and select Reset to default values.
3. Reboot your smartphone.

⚠️ Note: If after discharge APN Internet is completely lost, manually add a new profile APN. The parameters can be found on the website of your operator (for example, for MTS it is Internet.mts.ru with a login / password mts).

2. set up Wi-Fi for maximum speed

Redmi 9 supports Wi-Fi 5 (802.11ac) at theoretical speeds of up to 867 Mbps, but can default to compatibility mode with outdated standards.

Open Settings → Wi-Fi → Additional settings and follow the following steps:

• 🔄 Enable the option “Auto-connection to open networks” – this will speed up reconnection to known networks.
• 📡 Set "Wi-Fi mode" in the value 802.11ac (If there is no such item, your router does not support this standard.
• 🔒 Turn off Smart Network Switch – this feature can arbitrarily switch you from Wi-Fi to a mobile network, reducing speed.
• 📶 Enable "Improving location accuracy" - this improves connection stability.

If Wi-Fi speeds are still low, the problem may be in the router channel. Many low-cost routers default to overloaded channels (e.g., 6 or 11 in the 2.4 GHz band).

1. Go to the router control panel (usually at 192.168.0.1 or 192.168.1.1).
2. Find the Wireless Settings section (or similar).
3. Set the channel manually at 1, 3 or 9 (2.4 GHz) or 36-48 (5 GHz).
4. Save the settings and restart the router.

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If your router supports WPA3, turn on this encryption mode instead of WPA2. On Redmi 9, it works stably and can give you a speed gain of 5-10%.

3. Cleaning of system and background processes

One of the main reasons for the slow Internet on Xiaomi Redmi 9 are background applications that consume traffic and CPU resources.

• 📱 Messengers (Telegram, WhatsApp, Viber) – constantly synchronize data.
• 🎮 Online gaming (PUBG, Free Fire – can download updates in the background.
• 📊 Social networks (TikTok, Instagram) – autoplay video when scrolling the tape.
• 🔄 Cloud services (Google Drive, Mi Cloud) – synchronize files.

To limit their impact:

1. Go to Settings → Applications → Application Management.
2. Choose an application that consumes a lot of traffic (like TikTok).
3. Click Limit Background Activity and Turn Off Autostart.
4. For extreme traffic savings, turn off Background data (but this will block notifications).

It is also useful to clean the system cache:

1. Go to Settings → Memory → Cleanup.
2. Press Deep Cleanup and wait for the process to be completed.
3. Reboot your smartphone.

⚠️ Note: Do not manually clean the cache for system applications (e.g. com.android.phone or com.miui.home). MIUI.

Limit background activity of messengers |

Turn off auto-start for social media |

Clear the cache through the built-in utility MIUI|

Reboot the smartphone after the changes-->

4. Changing DNS to speed up loading of sites

By default, Xiaomi Redmi 9 uses your ISP’s DNS, which often works slowly or blocks some sites. Replacing DNS with public servers (like Google or Cloudflare) can speed up page loading by 20-50%.

Instructions for changing the DNS:

1. Go to Settings → Wi-Fi (or Mobile Network if you change for mobile Internet).
2. Click on the connected network and hold its name, then select Change the network.
3. Enable the option Additional settings (or Advanced settings).
4. In the DNS field 1, type 1.1.1.1 (Cloudflare) or 8.8.8.8 (Google).
5. In the DNS 2 field, type 1.0.0.1 or 8.8.4.4, respectively.
6. Save your settings and reconnect to the network.

To check the speed DNS can be used DNS Benchmark from Google Play. It's testing the available ones. DNS-The servers will show you which one works the fastest in your area.

5.Using an engineering menu for fine-tuning

On Xiaomi Redmi 9, you can manually configure the parameters of the communication module through the engineering menu, but this requires caution - incorrect changes can lead to loss of network.

To open the engineering menu:

1. Open the Phone app.
2. Enter the code ##4636##.
3. Select Phone Information (or Phone Information).

In this menu, pay attention to the following parameters:

• 📶 Set preferred network type - set up LTE only for priority 4G.
• 🔄 Enable LTE Only – turn on this option if you want to disable 3G/2G fully.
• 📡 Band Selection – if you know what frequencies your operator supports, choose them manually (for example, for MTS in Russia it is Band 3, 7, 20).

⚠️ Warning: Don't change settings you don't understand. For example, resetting Radio Band to factory settings may require flashing the device.

6. Update of firmware and system core

The MIUI factory firmware on Redmi 9 often contains bugs that affect internet speed. For example, MIUI 12.0.3-12.0.8 had a Wi-Fi driver problem that limited speed to 50 Mbps even when connected to a gigabit router.

To update the firmware:

1. Go to Settings → About the phone → System update.
2. Click Check Updates and wait for the search to be completed.
3. If an update is available, download and install it.

If the official updates don’t solve the problem, you can try a custom core (e.g. FrancoKernel or Kirisakura) that requires unlocking the bootloader and installing a custom recaveri (TWRP), but has the following advantages:

• 🚀 Optimized Drivers for MediaTek Helio G80, Reduced delays in data transmission.
• 📶 Support for additional bandings 4G (Band 28 for better coverage in rural areas).
• 🔋 Improved power management that prevents artificial speed limiting when battery power is low.

⚠️ Note: Installing custom cores will void the warranty and may cause the device to break. TWRP Make sure the kernel is compatible with your version. MIUI.

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Updating firmware is the safest way to fix software bugs that affect Internet speed. Custom cores give more growth, but require technical skills.

7.Alternative methods: IPv6 disablement and MTU optimization

Sometimes slow internet speeds are due to IPv6 or the wrong MTU (Maximum Transmission Unit) value, which is rarely mentioned in standard instructions, but setting them up can give a noticeable increase.

To disable IPv6:

1. Go to Settings. → Wi-Fi (or Mobile Network).
2. Click on the connected network and select Change Network → Additional settings.
3. Find the option. IP-setup and install IPv4 (instead IPv4/IPv6).

For MTU optimization (relevant at connection breaks or low speed):

1. Install the MTU Tools app from Google Play.
2. Run a test to determine the optimal MTU value.
3. If the test is less important 1500 (for example, 1472), change MTU Manually via Termux: su ifconfig wlan0 mtu 1472 (substitute wlan0 on rmnet_data mobile-internet).

These methods are especially useful if you are connected to a corporate network or using a VPN, where incorrect MTU settings can lead to packet loss and lags.

Hardware checks: antenna, SIM-card

If the software methods did not help, the problem may lie in the hardware:

• 📶 antenna Wi-Fi/4G — on the Redmi 9 If the body is deformed (for example, after a fall), the signal may weaken.
• 🪪 SIM-map -- the contacts oxidize over time. Try brushing them with a swallow or replacing them. SIM new.
• 🔋 Battery: When the battery wears out (capacity below 70%), the smartphone can artificially limit performance, including Internet speed.

To check the status of the battery:

1. Install the AccuBattery app.
2. Charge your phone to 100% and wait for the app to collect data.
3. If you look at the current battery capacity, if it's below 3,000 mAh (originally ~5020 mAh), the battery needs to be replaced.

If you suspect problems with the antenna, perform a signal test:

1. Enter the code ##4636## in the phone application.
2. Go to the phone information.
3. If it's below -100 dBm for 4G or -70 dBm for Wi-Fi, the signal is too weak.

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If hardware checks show problems with the antenna or battery, contact the service center. Self-repair without experience can aggravate the situation.

FAQ: Frequent questions about speeding up the Internet on Redmi 9