Hi, I have an Arc and sub for a 3.1.2 system. 

I have some speakers in the ceiling connected to a Gen 2 Amp for background music. 

I was thinking of connecting the amp as surround to the Arc, but: 

I am seeing conflicting information about Ethernet vs Wi-Fi. The Amp is connected by Ethernet to the router, the Arc uses Wi-Fi. Is this incompatible? Is do both need to be wired or both Wi-Fi? 

And I saw a suggestion that if I set up the Amp for surround use I won't be able to stream music anymore to it. Is that true? IE once a speaker is bonded as surround, it cannot be separately selected to play music? 

Thanks for your insight in advance.