Did you get my text msg? All I can suggest is slowing down. I know it defeats the purpose of a fast mower.
Maybe add some weight to the deck. Another thought is getting some shorter and or weaker springs. The deck itself if heavy as so it has to be spring tension issue.
You'll have to let me know how the discharge goes when the grass is thickens up and some damp. Im sure youve seen my posts and pics on here already.
I look forward to the vid.