Reply to Dj techtools s4 replacements?

Does dj ranking s accpets exchanges??? The knobs on my s4 over the past 2 months have gotten rediculously loose, the whole left part of my fx rack shakes when i touch a knob, does anyone know ranking s pollicy for this? I am going to call in the morning but its late so there not open so i posted for peace of mind.

Thanks joey