xdj 1000 mk2

Hi. I have 2 XDJ 1000 MK2 players and i can say it work great but after a few hours of working with them both of them get slow, i mean not just they load slow the tracks but even when i touch the back it stay more then 1 sec to get back. Also the qwerty is super fast at the begining and after a few hours i touch one letter and it apears on screen WAIT and 2 or 3 sec he doesnt show the next letter. I haven t done any update everything is original. Anyone with the same problem? Thank you. I m sorry for my english.