Volume fader jumping up - down

Hi!

I am using Rekordbox 5.8.5 with my XDJ-R1.

Did not use it for around a year by now and now I have a new problem. Pushing the left fader to the max, in the software it starts jumping fast up n down. I have to push pull fast to see what happens and if Im lucky, it will stay on max.

Never had this issue and no mather what USB cable I'm using. ALso tried it with a USB pendrive and no problem at all. 

But that is a problem, because I usually use it with a notebook.