Ways to get stereo out of Reactors

[RMK]

Hello, I’ve been trying learn how to connect 2 reactors without permanent wifi 
Signal.
I work onboard a cruise ship so I can’t have them connected to the ships wifi.
Ive seen couple ways you guys mention, but got confused
Ive seen toslink( dont know how it works
Sound card.. (i know how it works but I’ll prefer wireless)
I dont know if i can set them up with a router and get them to work with that router
But without wifi connection..
In the end i hope anyone can illustrate me on  some of this or other ways 
I can get them to work
Maybe with some advice on which other equipment i need to buy(best option
Thanks in advance!

Hello. With Toslink you plug it into one of your Reactors and the other one pairs wirelessly for Stereo. I just use my onboard / motherboard Mini Toslink Out on my PC to connect to 1 Reactor and the other one connects through the App on my phone.