Hardwire fire stick and Yamaha receiver to Extreme

[tkowalski]

I have ATT modem coming into house. I also a new extreme hardwired to modem about 10 ft away. About 30 ft away, I have an older airport extreme, extending the network. The older extreme is set up about 40 ft away wirelessly, from new extreme. I have an older yamaha receiver, that in order to stream music, it has to be hardwired to my older extreme, through the WAN port. I also have a fire stick, that I want to hard wire to older extreme. what is weird is, both work great, when they are connected to WAN port on older extreme. Apple confused the hell out of me, why that shouldn't work. Can someone in lay terms help me. I want to hardwire both the fire stick and receiver, somehow to the WAN port. They said it should not work if plugged to WAN port, but they both will only hardwire to older extreme, if they are plugged into WAN port. I already got the lecture of LAN vs WAN.