Best Ethernet Setup for Streaming Audio

I am streaming from an external drive on my Mac computer to an Auralic Aries, fed to an LKS DAC. I have a wired Ethernet connection from my wall outlet to an AT&T provided modem. The modem is connected to a Netgear router, which connects to a Netgear switch that is optimized for music streaming. Another Ethernet cable runs from my Mac directly to the Netgear switch. I am aiming for the best sound quality with this system. Here are my questions:

1. is it best to have my computer's Ethernet cable plugged into the switch, or should it be plugged into the router instead. It will function either way. But what would be the best option?

2. To provide optical isolation for the Ethernet cable, I installed two TP-Link FMC’s between the switch and the Aries streamer. Is that the best position for the isolation? I have it as close to the DAC as possible. Or should I place the FMC's somewhere else in the chain?

3. Would I obtain a boost in sound quality if I added a second pair of FMC's to the system? There are 4 other options: a. Between the wall outlet and the modem. b. Between the computer and the switch. c. Between the modem and the router. d. Between the router and the switch. In case it matters, the longest stretch of copper Ethernet cable is between the computer and the switch (50 feet).

Any suggestions would be greatly appreciated.