Isolation for Home Theater Speakers

Greetings fellow Agoners.I have my 42"LCD tv,center channel & front left/right channel speakers(all small sats) sitting on a wide cabinet.Today when listening to music at a fairly loud level I noticed that both the left/right speakers had danced their way accross the cabinet a small amount.I figure I had better put something under them to keep them stationary but can't decide wheather I should use something like Britestar Isonodes or Myrtle Wood Cuboids(with brass ball or without?).Your input here is greatly appreciated.
Get some Blu-Tack, that will cure the dancing.
Nobody out there had a similar problem?I don't want to couple the speakers to the av cabinet I want to isolate them from it.
They are isolated. That's why they are moving around. Blu-Tack.