Owners of popular budget smartphones like the Xiaomi Redmi 9 often face an unpleasant visual bug: the installed image on the desktop is spontaneously replaced by a standard or becomes black. This problem is typical of the MIUI shell and can occur both after a system update and as a result of third-party optimizer applications. Users notice that even after manually reinstalling the desired image, after a while it disappears again, which causes irritation.
The reasons for this behavior of the Android operating system in conjunction with proprietary firmware can be diverse, including the crowded cache of the system application “Themes”, and conflict with the “Wallpaper Carousel” function, and even errors in the launcher. In this article, we will discuss in detail the diagnostic algorithms and methods of troubleshooting to return the personalization of your device to normal without the need for complex reflashing.
The main reasons for resetting personalization
The first thing to understand is how the MIUI shell works, the system prioritizes resources from its own Themes store, ignoring images uploaded from the gallery if the settings indicate a conflicting source, and often the user does not even notice how the sync with the cloud or a third-party service that dictates its content terms has been activated.
The second common reason is aggressive memory management policies: When the internal storage space runs out, the operating system starts deleting the cached files, which include a thumbnail of the current wallpaper, and the next time the screen is rebooted or woken up, the system has nothing to display, and it puts a default plug on it.
⚠️ Note: Using memory cleaners and accelerators from unknown developers can forcibly delete system caches, including desktop design files.
If you have installed alternative shells like Nova Launcher or Microsoft Launcher, the problem may lie in their permission settings. The standard POCO Launcher or System Launcher launcher may lose the rights to read the file when you update Google Play Services components.
Checking the settings of the wallpaper carousel
One of the most common reasons why Redmi 9 has wallpaper is the active Wallpaper Carousel feature, which is designed to periodically change images on a locked screen, but due to software errors, it can apply changes to the home screen, and checking this setting is the first step in diagnosis.
You have to go to the settings and find the partition that controls the lock screen, and it's important to turn off automatic image change to prevent the service from interfering with your static personalization, and users often forget about this feature by accidentally activating it when they first set up the phone.
- 📱 Go to Settings and select Always on screen and lock.
- 🖼️ Find the wallpaper carousel option and go inside the menu.
- 🚫 Turn off the “Enable wallpaper carousel” switch at the top of the screen.
- ✅ Make sure the “Apply to Lock Screen” tick is also removed if it is available.
After doing this, it is recommended to manually install the desired image from the gallery. If the problem was in the conflict of services, then after turning off the carousel, the wallpaper will stop flying. In some versions of MIUI, the settings can be hidden deeper, so it is worth checking the Security app as well.
☑️ Diagnosis of wallpaper carousel
Cleaning the app's cache Topics
The Themes system app stores not only the uploaded designs, but also the data on the current wallpaper installed. If the database of this application is damaged or overcrowded, display errors occur. Clearing the cache and data is a safe procedure that does not delete your personal photos, but resets the store settings.
To perform this operation, you will need access to the application management menu. It is important not to confuse data cleaning and cache cleaning. In this case, we recommend doing both actions sequentially, as this is guaranteed to eliminate software glitches associated with file swapping.
Follow the following steps in strict sequence:
Settings → Applications → All Applications → Themes → Memory → CleanOnce the data is cleared, the app will return to the post-installation state, which means that your downloaded themes will remain in the account, but local settings will reset. Immediately after that, reapply the desired wallpaper through the standard personalization menu.
Conflicts with live wallpaper and video
Using live wallpapers or video backgrounds puts additional strain on the Redmi 9 processor and RAM. Unlike static images, they require constant rendering. If the system is running out of resources, Android can force the rendering process to end, replacing the background with a static image to save energy.
The MIUI shell works correctly with.jpg and.png formats. If you try to install an image in.webp or compressed via messengers (WhatsApp, Telegram), the system may not read the metadata of the file correctly, which leads to its rejection.
| Parameter | Recommended value | Problematic significance |
|---|---|---|
| File format | JPG, PNG | WEBP, HEIC, GIF |
| Permission | 1080x2340 pixels | 4K, 8K (too heavy) |
| Source | Local gallery | Online links, cloud |
| File size | Up to 5MB | More than 15MB |
If you use third-party apps to install video wallpapers, check their permissions. They may be banned from the background by MIUI Optimization. Try replacing the video background with a high-resolution, high-resolution, static image to rule this out.
Synchronization with Mi Cloud and account
Xiaomi’s ecosystem seeks to synchronize your preferences across devices. If you have other devices on your Mi Account, wallpaper settings may try to pull up from there, especially if another device (tablet or old phone) has standard wallpaper.
Check the sync settings in your account menu, and perhaps you have the desktop theme sync enabled, so disabling this option will allow each device to have a unique design that is independent of the user's actions on other gadgets.
- ☁️ Open Settings and click on your Mi Account at the top of the list.
- 🔄 Select Synchronization or Cloud.
- 📱 Find in the list of “Themes” or “Working table».
- ⛔ Turn off synchronization for these elements.
⚠️ Warning: Disabling theme sync won't affect your contacts, photos or notes. This action only affects the visual design of the interface.
Also worth checking is whether Subscription Themes or Automatic Theme Updates are enabled. In some regions, MIUI offers to update wallpaper weekly. Make sure that all auto updates are disabled in the Topics app in the Profile section.
Radical measures: resetting and reflashing
If none of the software methods worked, the shell's system files might be damaged, and in this case, resetting to factory settings helps, which is an extreme measure that requires all the important data to be stored beforehand, since the information from the phone will be deleted.
Before you do a full Wipe Data reset, try a less radical method, which is to reset your screen, and some versions of MIUI have a separate button in the display settings, and if you don't have one, you'll have to go all the way.
Procedure for complete discharge:
- Back up your data to Mi Cloud or your computer.
- Go to Settings → About the phone → Reset settings.
- Choose to erase all data and confirm the action.
- After restarting, set up your phone as new without immediately restoring a backup of your system settings.
In the most difficult cases, when the problem is caused by a bug in a particular firmware version (MIUI bug), it only helps to wait for an update from the manufacturer or install a global stable version through a computer. However, for Redmi 9, which has already received many updates, such cases are rare and usually involve interference with system files before.