I'm not sure if this is the place to ask this question, move it if it's not.

I'm trying to fix a wireless network. It only connects to a few devices and when it does work the connection is spotty. The router is a netgear wireless-n 150 wrn1000v2. Connecting to the router isn't a big problem, but connecting to the internet via WiFi is. I can't upgrade the firmware becuase it is from Comcast and it seems as though they only allow their versions of the firmware. I've monitored the network with wireshark and I see that the devices that are having trouble connecting are constantly asking "who is 192.168.1.1 tell 192.168.1.x" where x is the ip for the device. 192.168.1.1 is the router. This is from running wireshark on the wireless device. What does this mean. At this point I feel like buying a new router is the only option.