Hi Nigel,
thanks for your contribution to this thread. Yes, I’m one of those who have built a separate Network, included a dedicated contract with ISP from outside the house (fiber) and router used for music purposes only. Not only. I have experienced different switches (SR, Innuos PNET and recently NA Tempus. Not only. I also added a NA Muon Pro filter, from the switch to the streamer. Last but not least, I tried several Ethernet cables and ended up with STEALTH ULTRA (from router to switch) and Pink Faun Interlink (from switch to Muon Pro). Oh… I don’t use WiFi, completely disabled on the router, so my controller (iPad) is hardwired connected to the router. A Sean Jacobs PSU is feeding the router and router and switch (like all the other components) are grounded to a few CAD GC1.1 (one for each).
Overkill? Probably… It’s only rock and roll, but I like it!