SM-T335 Random vibrations after connecting to the internet

[Android Central Question]

after I connect to the internet (wifi or mobile data) the tablet starts to vibrate like it has a notification but nothing appears

it starts even if the wifi is only enabled but not connected

if I restart the tablet with the wifi and mobile data turned off there is no vibration ... but after enabling one of the 2 even without internet access the vibrating starts and won't stop until I restart the tablet

Sadly I can not really afford to do a factory reset (that's only the very last resort)

since it started no app has updated even though I can not exclude a rouge app behaving like this. is there anything that could show me what exactly is causing the vibration ?

Thank you

 

[Dano1200r]

Go to Settings, Sound and Vibration and make sure that it's off. Go to Notifications and make sure it's off. Clear your cache and reboot.