Hi @WokingBoy Go to Settings-Sounds and Vibration- Volume. Ensure the slides for Notifications and System Volume are set to an appropriate level. you may then need to check recent Notifications and check that the alert is checked for appropriate apps. An example for Gmail here:
Thank you but, unfortunately, the switch from sound to vibrate and back is continuous without anything else happening on my phone eg: no notifications, no messages, no calls. It just keeps going on and on and is driving me crazy.
@WokingBoy ok, thanks for confirming. you could try clearing the cache partition to see if that makes a difference :
Press the Power key to restart the device.
Factory Reset an option if all else fails though realise can be reluctance to do so,would need to ensure all Data is backed up obviously .
@bluetigon06: Please can you try restarting your phone in Safe Mode, and monitoring the performance to see if the issue occurs here? This will disable all third party apps, and help to determine if the problem is stemming form an external source. To proceed, press and hold the Power button until the 'Power off' prompt appears on the screen then release > Touch and hold Power off until the 'Safe mode' prompt appears then release > To confirm, tap Safe mode.
If your A52 5G no longer switches from sound to vibrate in Safe Mode, then restart the device as you would normally, and delete any recently installed apps. Sadly it won't be possible to tell which app is responsible, therefore please approach this via a process of elimination.