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

My Bluesound Node currently receives Wi-Fi, but I'd like to switch to a direct link. I assume that would be with an ethernet cable from the modem to the Bluesound - with possibly a better switch between the two.

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. 

Is there a piece of equipment or technology that I could help in this situation?