Echo/Delay/Verb Not working ?

I have recently bought a Pioneer DJM900Nexus 2

Strangely the delays/reverbs/echoes are not working when i use the fx selector via assign and when i use sound colour the echo and verb dont work either...?

All the other fx remain working ..

So i can get filters/sweeps on colour etc...and i can get roll, trans, phaser etc with selector...

So i have no idea why these particular fx via colour knobs and selector assign will not work...????

Any idea ?

Am i doing something wrong ?

Or is it a mechanical malfunction ?