I also bought 2 SPF fibre optical cages from Sonore and also 1 length of fibre optical cable. This is not Toslink cable I am talking about. The beauty of what I am doing is that the analog noise in the network from many sources cannot traverse the fibre optical cable. So in my opinion it does not matter what music server I use. I use a cheap DELL server that cost me about $600 to run ROON Core.
The Rendu's are ROON READY and all I need to do is hookup the fibre cable from the network switch to the opticalRendu and then from there take a USB cable to the DAC. For the microRendu I would use a RJ45 Ethernet cable from the same switch and then a USB cable to the other DAC.
The microRendu is using a switched more power supply and is supposed to be a bad way to do this. I will compare in 10 days the 2 rendu's and decide if I want to upgrade the microRendu also with a linear power supply or replace it with another opticalRendu.
I bought the following gorgeous network switch to make this possible. It has 2 fibre optical cages along with a few RJ45 slots, cost was $199.
https://www.ui.com/unifi-switching/unifi-switch-8-150w/
Send me a PM if you want to discuss this approach further. I can point you to some links.