An entire Ethernet cable infrastructure of SSTP can certainly help prevent the creation and propagation of RFI... and given that SSTP only costs a little more than UTP, it's an advisable investment.

It's worth remembering that one of the biggest causes of RFI creation in the household's of today is the sending of Ethernet data at ~100Mhz (Gigabit)... and in today's household's there is much more data being distributed at high speeds than even 2-3 years ago [e.g. Netflix, Online Gaming, Video Streaming all result in Data Usage at rates that are orders of magnitude higher than what existed even 2-3 years ago... and it is this Data speeding around at 100Mhz that is causing the dramatically higher levels of RFI in people's households today, as opposed to previously.

Having said that, using some SSTP for the typically short connection to the Endpoint can help prevent the migration of RFI into the Endpoint and this small and very cheap step on its own can yield positive benefits.

As Switches are also useful to prevent migration of RFI around a network (and as discussed here before several times), it's good practice to place all the Sooloos Audio components on their own Switch, and to keep other high data usage items (Game Consoles, Video Streamers, PC's etc.) off that Sooloos sub-network.

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