How to secure my Hydrohoist to my dock

[Stillcreek]

I recently purchased a used, side mount Hydrohoist lift and attached it to my dock using the factory that allows the lift to rise and fall. I live on a river with much summer traffic and Unending waves. As a result the lift is constantly banging away on the dock. Anyone know of a way to dampen the impact between the dock and lift?

Thanks!