Two DACs + One Amp

I have two DACs and I want to connect them to my Schiit Magni Heresy using this adapter. I use one DAC at a time, So only one DAC is turned on at a time, The other DAC is turned off.

Will everything be alright in this setup ? Will the signal degrade or weaken ? anything wrong with this setup ?

I’m must be missing something. The Hersey has RCA inputs, right? So why the 3.5mm split?
Do the DACs you have not use RCA out?

If they do have RCA out puts and you don’t want to invest in a switcher box you could try something like this.