Our JV3 prints too much black

We Guys, who knows the answer? Our JV3 with SS2 inks prints too much black. All other colors are good, but the black will make a sort of 'balloon-effect' on the film. We prints on Arlon DPF6000 with ONYX. We currently use the original Arlon DPF6000 ICC profile and the color output is perfect except ...