Hoping someone can find a solution here... My zero turn is only 4-5 years old and mowed great for the first two years. It’s been progressively getting worse for mulching. I know a good amount about landscaping and have exhausted all options I can think of. Brand new, used to mow at 3/3.5 and had a terrific lawn. Today I have to double cut and still leaving a lot more clumps than there should be, unless I leave it over 4”. I’m aware of the 1/3 height rule, wet lawns, clean underside etc. I tune my mower every year- filters, oil, spark plugs, battery, blades, etc. (brand new mulching blades a few weeks ago). I decided to take it in to my dealer and they replaced the deck belt, said everything is running great. I’ve gotten to point of considering a new mower if I can’t figure this out. My walk behind Honda does a superior job compared to my toro. Any help would be appreciated. Thank you.