And how close are you to your neighbors, panther, distance-wise? Wonder if they installed something recently ... Did you try a new Ethernet Cat6 cable between the incoming modem (which one do you have, cable, fios, etc) and the router's WAN port? Sometimes cables start to go bad without notification. Shut down any other routers you have while you test. Otherwise, I agree, the unit itself is likely suspect.
I don't think you can use the TV's USB ports to establish Wifi connections, only for content from attached devices, but worth a try if the menu system offers that choice.