I would say the weight idea also.. I would make a mold of the top of the projector, and get some led, and melt it so that I would have a good fit with some double sided tape.
the bolt idea that Zimm said, will most likely not work due to the bolt going though the stud, and then to the projector, so the bolt will still be a sound or vibration short.
you would need to do something similar to a motor mount, with 2 studs that go into a common rubber mount, but the 2 studs are not physically touching. something like this.
http://www.rubber-group.com/isolationmounts.html
