Isolation Devices, Something to put on top of unit

Hello, I need to find a good device(s) /or/ method to kill the airborne vibrations that attack the top of my cd player and preamp... Basically the shelfs under the components are completly dead, you can not feel anthing coming thru the rack or the bottom of the units, its just the top plate of the unit, which is the largest and weakest surface area anyway... but again the rack is excellent, it has 3" thick maple shelfs and with full bass in the room does not show a hint of vibration. Don't get me wrong the system sounds excellent and never skips or does anything funny because of the top plates dancing to the music, but of course I would like to eliminate this.
-Should I just get some 2" solid maple blocks that fit on each unit and do it this way as this is how the shelfs are, with like a sheet of fabric inbetween or something?
-I would like to keep this situation as CHEAP as possible, again I would like the benifits but really the system performs flawlessly.

--I have a turntable in the system too, it never skiped once at full output so its good, the plater does not vibrate, just the dustcover(so I just leave it open

--Wadia CD player never has a problem but would like to put something on top. It does not get hot.

--Mcintosh Pre-amp like to put something on top, it does not get hot.

Thanks fellow audio people