OK...here is one point of view. (I'm sure you will get the other one too).
Phono pickups develop their signal by vibrations of the stylus caused by the record groove. Obviously any other source of vibration will also cause the phono pickup to generate a spurious signal. Virtually all phono playback systems have this problem to some degree. In my system mechanical vibration effect is (as far as I can tell) zero, but I still have acoustic vibration (sound) which makes the vinyl LP vibrate like a drum skin. Various record clamps have been developed to minimize this problem. The best solution is a vacuum system that draws the LP into solid contact with the turntable, so it isn't flexible any more.
Vacuum tubes have various internal pieces, the exact spacing of which determines parameters of the tube, like gain. Vibration causes these pieces to move, and that generates a spurious signal. This effect is called microphonics, because the tube acts like a microphone. This problem can be almost completely eliminated by good equipment design and reasonable placement. High gain tubes, in preamps and the input stages of power amps are most likely to exhibit audible microphonics.
It is claimed that transistors, capacitors, resistors, and even wires can exhibit microphonic effects. With the possible exception of some types of capacitors exposed to severe vibration I know of no scientific basis for the claims. Few inductors are used in today's audio circuits, but a defective one, with loose wire, could be microphonic.
It is claimed that vibration degrades performance of digital equipment such as CD players. The mechanism for this degradation is supposedly errors in reading the digital data. Indeed, vibration might defocus the optics and degrade the signal so that a "one" is misinterpreted as a "zero" or vice versa. However, some errors like this are expected, and the digital information on the CD is encoded for error correction. Unless the error rate exceeds what the error correction algorithms are designed to deal with the information is recovered without errors, as if no transmission errors had occurred. (An analogy would be my spelling mistakes in typing this post. After I run it through my spell-checker, can you tell whether I made any errors when I typed it?).
Speakers present an interesting situation: some feel that they should be isolated, for example by hanging them from the ceiling on chains, while others strive to "couple" them to a solid floor with various devices, often cones. (I'm in the isolation camp). The notion that a few ounces of vibrating driver cone could move a suspended fifty pound speaker enclosure is absurd. What does happen is that flat panels of the enclosure can vibrate because of the pressure changes internal to the enclosure, but this problem relates to internal bracing of the enclosure and is unaffected by how it is mounted. Although the enclosure panels move much less than the speaker cone, they have a lot more area than the cone, and can radiate a significant part of the sound emitted by the speaker system. If you choose to couple the speaker to the floor, three (not four) cones would be best to avoid rattles.
I bet this post will get some of our friends all shook up!
