To help w/the thin cover on my Rotel CDP I first covered the entire cover (side>top>side) w/one piece of dynamat. I then cut an old Rega plinth to fit the top & after plugging the holes w/filler, put that on top then added some old lead leg weights on the plinth.
I have commercial absorption/isolation stuff underneath & the combo of everything together vs. nothing at all has helped lower the noise floor, which has resulted in letting me hear a little more detail & layering plus a slightly bigger soundstage.
I've done some stuff inside the CDP too but just the weight on top by itself at the very least keeps my somewhat large DIY PC from moving it off the Herbies grungebuster balls.
I have commercial absorption/isolation stuff underneath & the combo of everything together vs. nothing at all has helped lower the noise floor, which has resulted in letting me hear a little more detail & layering plus a slightly bigger soundstage.
I've done some stuff inside the CDP too but just the weight on top by itself at the very least keeps my somewhat large DIY PC from moving it off the Herbies grungebuster balls.