Vibration problems are so much fun.
Here's what I suggest, see if you can use either of Chief�s CMA-347 Projector Vibration Isolator or CMA-345 Structural Ceiling Adapter with Decoupler. If you can't or that doesn't work visit Vibration Mountings and Controls, Inc. @ http://www.vmc-kdc.com/ and go to their Vibration Hangers section or Pad Mounts. Any of these options should help you resolve the problem, but before you do any of this try to measure the amount of deflection you are getting that will give you a real clue of the correct product to use.
Hope this helps.

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