Network Switches

@kirkwallace 

You could get a SFP switch, and simply use fiber from your modem on out.

I have also looked at the Sonore options, but found if not using an "optical streamer" ie the optical Rendu, two optical modules were needed ( per Andrew Gillis).  One to convert the ethernet to optical and then another to convert back to ethernet.  Too many boxes and too many power supplies/wall warts.  I would prefer a simpler, one box solution.

@devinplombier that is very interesting. So, just to make sure I am follwoing, as i am quite inexperienced with network technology and options, this means getting a switch that can take ethernet RJ45 (say Cat6a) from the router and has one or more SFPs ports built in that i could attach fiber optic cable (say LC) to, but as the Roon and my M33 don’t have any ports that accept fiber (LC or otherwise) inputs, wouldn’t i still need media converters?

You would need converters at every component that does not natively support SFP.

Typically, the last Ethernet segment - the one that plugs into your streamer - is where optical decoupling is most beneficial if sound quality is the goal.

@devinplombier , got it; makes total sense. Thank you. 

I have returned the iFi silent power unit and for now, i am going replace it with a  duplicate the double StarTech/Finisar optical “moat” with the OM4 Corning glass in between the switch and M33 (i.e, the last ethernet segment to use your nice phrase). I may just leave the connection between the modem & router, alone for now. (I put aslightly better power source in to the router a couple weeks ago; maybe that is sufficient, given the “moats”.)