I just got spectrum's internet and phone because AT&T could not provide the bandwidth compared to spectrum. My main (Spectrum) Router/Modem resides in the garage in the middle of the house. I have a Netgear Wifi extender in the house which provides all of the all automation equipment (Smarthings hub, insteon hub etc. as well as wired ethernet connections (TV, Directv, Insteon Hub etc). I also have a netgear switch which handles all of the traffic of these wired devices and has one cable going to the netgear wifi extender. The Netgear wifi extender is not that far from the main router. Signal is great but with the 2Ghz and 5ghz extending the 2 ghz keeps crashing causing me to have to re-boot the extender and sometimes the spectrum router will need a reboot becasuse the 2ghz is not working. Is this a common issue with this spectrum equipment and the netgear routers? Do I need to get a different extender that is more combatible with spectrum equipment? My Television which is hardwired will stop working with Netflix when this issue happens and it is hardwired via ethernet.
It seems that your entire LAN is connected by ehternet sans the "extender" you need.
Take the wireless out of the euqation, and use a pair of ethernet powerline adapters to connect your gateway / router to the switch that connects to everything else. They are cheap and perform quite well, especailly if both powerline adapters are on the same circuit or pole. A starter kit, which consists of a pair, typically runs under $50.
I recommend everything in your home that is not carried around with you be wired, except for the "smart" things in your house like thermostats and switches.