Xiaomi
Sound and Vibration for Calendar Reminders auf Xiaomi
Calendar reminders on Xiaomi phones rely on the notification permissions of the Calendar app itself, not just the general ringtone or system volume. If a reminder for a birthday or meeting does not play a sound or vibrate, the app-specific notification channel is often turned down or the sound was never assigned.
The setting sits inside the Calendar app rather than in the general phone sound menu. Open Tap on Calendar ➔ Open the Menu ➔ Tap on Settings ➔ Tap on General ➔ Enable or disable Notify on this device ➔ Tap on Calendar notifications ➔ Set the Notification sound and turn on/off Vibration.
Once Notify on this device is enabled, the Calendar app is allowed to send alerts through the system. From there, the notification sound and vibration can be adjusted independently, so you can pick a distinct ringtone for appointments or mute them while keeping other app sounds active.
If reminders still stay silent after this is set up correctly, check whether a Focus mode or Do Not Disturb schedule is active. Those system-level modes can override app notification sounds even when the Calendar settings themselves are correct.

