How do I switch from Wi-Fi to Ethernet cables?

You can use a Wi-Fi extender or a mesh system, plug extender or mesh node into the room where your system is located and run an Ethernet cable from the node to your streamer.  Works well. 

Ok, yes, @soix I was wondering about a mesh node or extender. Given that either of those also rely on Wi-Fi it would seem (on the surface) that this wouldn't really accomplish anything. However, I am wondering if a high quality ethernet switch between a mesh node and my streamer could result in better sound quality than just wi-fi to my streamer. 

imaninatural

The problem is that my modem is in the basement and the Bluesound is on a different floor. There is not a clear path for running cable. 

I've had issues like that and been amazed at what a pro installer could do to fish wire. A good electrician or network/alarm system installer can often work wonders. It's worth having one evaluate your situation.

I hear ya, and on the surface it doesn’t make much sense but it works.  Many people here with $$$ streaming setups swear by them.  My guess is that hardwiring the stream prevents the streamer from having to use circuitry to process the Wi-Fi signal over the air, but that’s just a guess on my part.  The good news it’s not all that expensive (in audio terms anyway) to give it a shot and if it doesn’t provide significant improvements just return it.  And yes, I believe inserting a quality switch, optical connection, etc. between the node and streamer could yield further meaningful improvements, but I’m sure someone here who’s actually done this could chime in further with more direct specific info.  The one thing I’ve learned is that with streaming everything matters — and matters A LOT — so there are lots of ways to engineer in further improvements, which is at once exciting and daunting.  Just my $0.02 FWIW, and best of luck.