I also have a Salamander S30 rack (with side panels and a door). Besided the recommendations for isolation platforms, I'll suggest isolating the shelves from their brackets (I use some Herbie's dots), and adding mass to all of the shelves. If yours has side panels or a door, you can apply rubber tape or caulk to the seams to eliminate vibrations. Just tap on all the surfaces to figure out where it's needed.
CD isolation platfroms
I'm considering an isolation platform for my Ayre C-5 XEmp. I recognize that my current equipment stand, the Salamander Designs S30, is far inferior to the more elborate equipment stands availabe but it compliments my Mac electronics quite nicely. The Ensemble Zobro isolation platform is at the top of my list but I'm looking for other suggestions/alternatives. Thanks in advance.