So I moved things around and my digital signal path is now cable in > modem > router > Silent Angel Bonn N8 switch > Gigafoilv4 > Network Acoustics eno > Mojo Audio server/streamer > Mojo Audio DAC…
The modem and router are powered by two separate DC outputs from a single HDPLEX 100W LPS and the switch and Gigafoilv4 are powered by one each of these 5V LPSs that seem to work quite well for 5V peripherals.
All Ethernet cabling is good quality CAT8 with gold connectors except the run between the Gigafoilv4 and the eno, which is Network Acoustics’ own eno Streaming Cable, and from the eno to my server/streamer, which is the short, captive eno Streaming Cable.
The Gigafoilv4 provides optical isolation just before the eno and streamer/server and is much more convenient than using dual converters and a separate optical cable. The eno provides further isolation using transformers and I am not sure whether this is redundent with the Gigafoilv4.
The Bonn N8 switch is currently located near the modem and router but I also have the option to run the Ethernet cable directly from the router to the Gigafoilv4, without the switch. I may try that option later. I honestly cannot say whether this reconfiguration and adding LPSs has been an improvement, but the system sounds good.