Muting Volumio when booting Raspi

Dear friends of quality sound,

I love my Volumio. Yes, I really do.

But one thing nags me each time I am booting the Raspberry: It’s the 30 seconds or so until the Volumio screen shows up. While the Raspi is busy in the booting procedure it is accompanied by scratching sounds coming out of my old KEF Calindas. This sounds like an old tube radio with some bad welded junctions when you tap the housing. Really annoying half minute.

When the Volumio interface finally is up and working, all is fine.

So here is my question you might have already guessed from the headline:

Is there a trick or a switch or both to suppress this ugly sound and mute Volumio until all is set and done?

BTW here is my setup: Raspberry Pi 3B, HifiBerry DAC+, 2 x 250W Amp, 2 x KEF oldschool