Thanks for your reply.
You got perfectly the point.
So do you think is not the case to ask for a warranty change?
Because as you wrote, it seems that is a common issue
I'm pretty sure it's not a replaceable warranty issue, it's just the way the Pro3 works, I think it's just a Sequential thing.
I actually came up with a (dumb, diy) fix for it. When you change the Cutoff and are going to go work on the sequencer, or something else, tap lightly around the filter cutoff knob to encopurage it to "settle".

-- Then move on to other work
I've been really disappointed that the buyout by FocusRite hasn't meant getting some help on the Firmware/Software for Sequential. They obviously need it.