Depends what all digital means, digital sources with DACs and analogue amplifiers, or is it digital all the way to the 'speaker?

My experience is that decoupling and/or coupling make a difference with turntables (huge), CD players (not a lot), phono pre-amps (a bit, microphonic if you tap them, but that's not normal operation) and loudspeakers.

I've never used a valve amplifier, but they are very microphonic so I'd imagine supports are important.
Anything analogue can be subject to microphony, but with solid state electronics it shouldn't be an issue, if it was such a big deal, all active loudspeakers (including DSP) with the electronics built in would be terrible and would not be made.