Tempo fader DDJ- RB glitching (even after replacement)

Hello, 

I have owned a DDJ-RB for some time now, but the last few months my B-deck tempo fader has been giving me problems.

It seems to glitch, the BPM is not correct and it keeps changing even though I am not touching the fader.

So yesterday I replaced it myself (I have soldering experience) but it still does not seem to work.

What could it be, is it worth repairing it myself?
Buying a new one is not an option for me due to financial reasons.