Network Switches

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”.)

The original GigaFOILv4-INLINE (here) was basically an optical isolator, similar to the LHY product. The same folks that brought us the GigaFOILv4, DJM Electronics, now offers the fancier looking, Streaming Audio Ethernet EMI Filter (here) that uses “proprietary Digital Signal Processing (DSP) techniques” and costs about 4x as much.  Maybe it works better. Does it work better than the Network Acoustics ENO 2 that uses transformers to isolate, or the more expensive MUON PRO?  Who knows? Two $30 converters and two $80 LPSs may perform just as well, or not.  I have tried multiples of these things in my own system and the only thing I learned for sure is that they just keep costing more. In the end, we all seem to find our own path.