Missing calls on your Xiaomi 15 can be a real headache, especially when you're expecting something important. The phone sits silently while notifications for missed calls pile up. This usually comes down to a setting that got changed or a small software hiccup in HyperOS 2.
Let's run through the most effective fixes to get your ringer working again. I'd start with the volume and silent mode checks first, as those are the most common culprits.
Check Your Volume and Silent Mode
First, unlock your phone and press the volume up button on the side. Make sure the volume slider that appears shows the media or ringtone level increasing. Sometimes the volume for media and notifications can be set independently.
Also, check if your phone is in silent or vibrate-only mode. Swipe down from the top of the screen to open the Quick Settings panel. Look for a bell icon with a slash through it or a vibration icon. If you see either, tap it to switch back to full sound mode.
Review Your Do Not Disturb and Focus Modes
HyperOS has several modes that can silence calls. The main one is Do Not Disturb. Open your Quick Settings panel again and look for a crescent moon icon. If it's highlighted, tap it to turn it off.
For a more detailed check, go to Settings > Sound & vibration > Do Not Disturb. Here, make sure the main toggle is off. Also, look at any schedules or rules that might be turning it on automatically at certain times or in specific locations.
Change Your Ringtone
A corrupted ringtone file can sometimes cause no sound to play. Try switching to a different one to test. Go to Settings > Sound & vibration > Phone ringtone.
Select a new, built-in ringtone from the list. After you choose one, have a friend call you immediately to test if it works. This is a quick way to rule out a problem with your current sound file.
Disconnect Bluetooth Accessories
If your Xiaomi 15 is connected to a Bluetooth speaker, headphones, or your car, incoming call audio might be routed there instead of the phone's speaker. The easiest fix is to temporarily turn Bluetooth off.
Swipe down for Quick Settings and tap the Bluetooth icon to disable it. You can also go to Settings > Connected devices > Connection preferences > Bluetooth and toggle it off. Test a call with Bluetooth disabled to see if the ring returns.
Check for Blocked Numbers
Calls from blocked numbers won't make your phone ring. It's worth verifying you haven't accidentally added someone to your block list. Open the Phone app and tap the three-dot menu in the top right, then select Blocked numbers.
Review the list. If the person trying to call you is on it, tap the remove icon next to their number. After unblocking them, ask them to try calling again.
Disable Call Forwarding
If call forwarding is active, your phone won't ring because the call is being sent to another number. To check, open the Phone app and tap the three-dot menu. Go to Settings > Call forwarding.
Make sure all the options, like "Always forward" or "When busy," are set to off. If any are enabled, your calls are being redirected before your Xiaomi 15 even has a chance to ring.
Turn Off Silence Unknown Callers
Xiaomi has a feature to automatically silence calls from numbers not in your contacts. This is great for stopping spam, but it can also silence legitimate calls. To check it, go to the Phone app's settings again.
Look for an option labeled "Block unknown calls," "Silence unknown callers," or something similar. The exact name can vary in HyperOS. Turn this feature off temporarily to see if it resolves your issue.
Verify App Permissions for Dialer and Contacts
The Phone app needs the correct permissions to function. Go to Settings > Apps > Manage apps. Find and tap on "Phone" or "Dialer" in your app list.
Tap on Permissions. Ensure that permissions like Contacts, Phone, and Microphone are set to "Allow." Without these, the app might not be able to process incoming calls correctly.
Restart Your Xiaomi 15
A simple restart clears out temporary glitches in HyperOS that could be interfering with the ringer. Press and hold the power button until the power menu appears, then tap "Restart."
If the screen is unresponsive, you can force a restart. Press and hold the power button for 15 seconds or more until you feel the phone vibrate and see the Xiaomi logo appear. This forces a reboot and often fixes minor software issues.
Check for System Updates
Xiaomi frequently releases updates for HyperOS that fix bugs. An update could resolve a known issue affecting ringtones. Go to Settings > About phone > HyperOS version.
Tap on "Check for updates." If an update is available, make sure your phone is connected to Wi-Fi and has at least a 50% charge before downloading and installing it. I've seen updates clear up odd audio problems more than once.
Reset App Preferences
This resets all your app permissions, notification settings, and default apps without deleting any personal data. It's a good middle-step before a full reset. Go to Settings > Apps > Reset app preferences.
Tap "Reset apps" on the confirmation screen. Afterward, you'll need to re-grant permissions when you use apps for the first time, but it can resolve conflicts that stop the Phone app from ringing.
Disable Any Third-Party Theme or Launcher
If you're using a custom theme from the Themes app or a different launcher like Nova or Lawnchair, try switching back to the default Xiaomi launcher and theme. Some deep system modifications can accidentally break core functions like ringing.
Go to Settings > Home screen to set the launcher back to "System launcher." Then, open the Themes app and apply the default "Classic" theme. Reboot your phone and test a call.
Check the SIM Card
A poorly seated or faulty SIM card can cause call issues. Turn off your phone and use the SIM ejector tool to remove the SIM tray. Take out the SIM card, gently clean the gold contacts with a soft cloth, and reinsert it firmly.
Make sure the tray clicks back into place securely. Power your phone back on. If you have another SIM card handy, try swapping it in to see if the problem is with the card itself.
Perform a Factory Reset
If nothing else has worked, a factory reset is your last software step. This will erase all data on your phone, so you must back up everything important first. Use Xiaomi Cloud or transfer files to a computer.
Once backed up, go to Settings > About phone > Factory reset. Tap "Erase all data" and follow the prompts. After the reset, set up your phone as new without restoring a backup immediately to see if the ringing works on a clean system.