s5 mediaserver randomly shot up without installing or downloading anything

ok, so sometimes i change my simcard to get LTE connection when i really need it cuz the provider I use for txting doesnt provide decent LTE here in my country and i have it on a plan so thats what i mainly use, today i needed to use LTE, I was using my phone with mediaserver on a normal % like 3% or something, when i changed sim it shot up to 40% and dont know what to do, i think it might also be because i removed SD card while removing sim because it proved abit troublesome without removing the SD card.

solutions i have tried :
deleted .thumbnail
disabled media storage
downloaded and used media killer
removed SD card and rebooted

i had this problem 2-3weeks back and decided to format my phone, wouldnt want to resort to this again :(

any help appreciated thanks!