Metronome on CDJ

I think rekordbox's beat gridding is quite poor.
Even manually adjusting it directly on the CDJs half the time the beats are still off even though they visually look spot on with the red & white markers.

I'd like to see a firmware which would allow a metronome tone audible in the headphones when in beat grid mode of the CDJs to ensure a more accurate beat grid.

Traktor does this very well - hoping Pioneer can bring this feature out.