Home network Fibre optic vs Ethernet

It's like Wireless does not exist. Get a good wireless mesh network and stop listening to the worries of people concerned about the metal in their power plugs. Unless you have $1M system do you think your Ethernet connection is the biggest issue you got? Even if you have a $1M system I doubt it is.

@tvrgeek has his head on straight.  Ethernet is not going to make a ground loop unless you use a shielded cable which is what the audio paranoid are most likely to tell you to do. 

WIfi mesh. 

Do you think the Internet connection to your system is the biggest problem you have? Maybe if you had dial-up. Go buy some better speakers and stop worrying about fiber or wired. Bigger fish.