HTC One M8 randomly vibrates. Help!

[Frenk Dragar]

So here's the deal: every 2-3 hours or so my (somewhat new) phone vibrates in a short burst of 2-3 vibrations.
I have looked through some forums and found no solutions (yet).

Thank you for your help in advance!

 

[licsinmex]

My s4 was vibrating too and what I did is in app settings, I deleted all Facebook data and it stopped vibrating. Unbelievable I think I found the problem

 

[B. Diddy]

Welcome to Android Central! It may be due to some app that is set to give you notifications. Go through all of your apps and open their respective settings menus. Look to see if any are giving you vibrate notifications that you don't want.

 

[Frenk Dragar]

Thanks, i guess i'll try the facebook thing.

 

[Frenk Dragar]

Update: The facebook thing doesn't work, the phone still vibrates and no notifications show up.