computer isolation

my mac mini and nas both are on vibrapod footers and resting on a thick maple butcher block....it can't hurt

I'll go out on a limb and say no. If you're output is a digital signal then no for sure and if your outputing an analog signal then I doubt there is any level of isolation that could improve the signal.

Unlikely unless your laptop has tubes or uses a stylus to read a vinyl groove. Modern electronics is not micro-phonic. Frankly, if it was a problem then passive speakers would not work as the crossover would pick up vibration.

Just another urban legend.

Urban legend? I do not know if it will make a difference, but most all electronics are sensitive to vibrations as they have capacitors aka condensers- as in condenser microphones amongst other things.

Crossovers are micro phonic as well, just less perceptive as the signal is very small relative to the load. The Tannoy DMT series of studio monitor loudspeakers for instance. DMT was market speak abbreviation for Differential Material Technology. The capacitors were all wrapped in a butyl rubber type (mortite?) compound that had heat shrink tubing around it to help suppress the vibrations.

How much of this effects the output is up for debate. Acting as if it does not exist is a falsehood. Physics has not changed, only our applications of it. As for the OP's question, there are probably more important things to try to optimize in you computer audio rig.