If you've used the same blade on your cutting machine for lots and lots of cutting, and you start to have problems with the quality of the cuts on your cardstock, chances are the blade needs changing.
Don't waste your time with adjustments of the blade or the software settings, just realize that replacing an old blade with a new one is the way to fix the problem.
Don't spend hours ruining cardstock with a dull blade, while the cats need to be fed and litterboxes need to be cleaned.
And don't ask how I know all of this.
You're welcome.