Here’s a long-shot guess that might help: You might be assigning the wrong things to your Quick Knobs.
After you apply a range to a parameter, that parameter will stay within the specified range if varied using the hotknob you have assigned to that range (one of hotknobs P, A, or B).
To vary a hotknob within the specified range using one of the three Quick Knobs on the face of your H90, you have to assign a Quick Knob to that hotknob using the Control Assignments page of H90 Control. If that is done properly, “P hotknob” “A Hotknob” or “B Hotknob” will be displayed next to the assigned Quick Knob and the parameter value will stay within the specified range when using that Quick Knob. Here is where things can get tricky …
It is also possible to assign a parameter itself to a Quick Knob even if you have applied a hotknob range to that parameter. If you assign a Quick Knob to the parameter itself using the Control Assignments page of H90 Control, the parameter name will be displayed next to the assigned Quick Knob and the parameter value will NOT stay within the specified range when using that Quick Knob.
For example, if you create a delay time range for Digital Delay parameter “Delay A” and assign that range to Preset Hotknob A, please make sure the display next to your Quick Knob does NOT say “Delay A”. The “Delay A” parameter value will only stay within the desired range if the display next to your Quick Knob says “A Hotknob”.