I bought the R7000 in mid-November. Client workstations periodically lose connection with the router. Power cycling the router will normally allow you to reconnect. The problem has become progressively worse. Yesterday, I updated to the latest firmware. The router worked OK overnight but now won't allow any connections (wired or wireless) and restarting it isn't helping.
My guess is the firewall is blocking or preventing internet signal thru to the R7000. As a test can you remove the firewall from the network and connect a PC hardwired to the R7000 and test that machine for connection reliability???
I found a forum for your firewall, although it gives one's experience on how to block certain IP Address's, this may give some idea if you have the firewall config'd, may want to double check firewall settings as well.
No. I'm not getting that far. Workstations cannot connect to the Netgear either with wireless or wired connections. I can't even get to the web interface of the router when I'm plugged directly into it.