Sorry to be posting this in the medium format section, since I don't own a back and am using C1 LE at the moment, but I highly recommend going into File/Preferences/Processing Settings/ and checking the box that states "Use pre 3.7 Standard Color Noise Suppression."
I think this color noise suppression is MUCH better than the new suppression that you control with the slider. Therefore, with this option checked, the slider doesn't affect any color noise suppression settings. Just keep that box checked, and you'll get nice, fine grained noise, no color noise, and no weird artifacts in shadows from the suppression which I experienced using the slider, instead of pre 3.7 suppression. Just my preference.