CDJ2000 Tempo Reset button coming on by itself inttermitently

Hi,

We have a pair of CDJ2000's and on the left deck (deck2) all of a sudden the tempo reset is intermittently enabling itself when a track is playing and thus adjusting the pitch back to "0" and it makes it near impossible to mix and it sound awful and is so noticeable. When you press the tempo reset button it does not engage the function and to disengage it you have to engage the Master Tempo button button but it does not stop it happening again. Does anyone have any knowledge of this or ideas please? Thanks