https://community.sony.rs/t5/xperia-archive/sudden-vibration/m-p/3159911#M331564 <P>Do you have any app acting up(battery savers,task killers etc)?Try a force shut down(power button+vol up until the phone vibrates 3 times).Turn it on normally after.</P> Wed, 29 Jan 2014 15:50:06 GMT _alexdon_ 2014-01-29T15:50:06Z https://community.sony.rs/t5/xperia-archive/sudden-vibration/m-p/3159910#M331563 <P>Can anyone tell me why my z1 vibrates every some minutes during ıt is in stand by mode (screen is off and no using).it vibrates some times evety 5 minutes some times much more longer.Each time i think there is new massage but actually just a simple vibration??? i think it was like this from the&nbsp;<SPAN>beginning not so sure.gps is off also.stamina mode is on usually.</SPAN></P> Wed, 29 Jan 2014 15:42:32 GMT https://community.sony.rs/t5/xperia-archive/sudden-vibration/m-p/3159910#M331563 z1-Happy2 2014-01-29T15:42:32Z https://community.sony.rs/t5/xperia-archive/sudden-vibration/m-p/3159911#M331564 <P>Do you have any app acting up(battery savers,task killers etc)?Try a force shut down(power button+vol up until the phone vibrates 3 times).Turn it on normally after.</P> Wed, 29 Jan 2014 15:50:06 GMT https://community.sony.rs/t5/xperia-archive/sudden-vibration/m-p/3159911#M331564 _alexdon_ 2014-01-29T15:50:06Z