ddj sx2 fx not working

Hi, i just bought a pioneer sx2 and now i want to try the Fx but none is working.

Example: Deck 1 is playing ...i have selected the brake effect, "Fx 1" button is on ...but i cant hear anything. Thats the same for deck 2 and fx2 button selected. I have tried everything, but now working. 

Any solution ? p.s Using Serato DJ 1.9