I have Verizon FiOS with an Actiontec MI424WR router. The system has been in place for a number of years with a couple dozen devices connected via wireless, hardwire, and coax (using MOCA to connect to a switch in another building).
The router's address is 192.168.1.1, and its DHCP address range is 192.168.1.2 through 254.
The other day, one of the devices, a Chromebox reported that it was connected to the network, but couldn't access the internet (whether wireless or hardwired). It was set to automatically configure, and I noticed that it had been assigned an IP address of 192.168.10.100, and that the gateway was 192.168.10.1. As noted above, this is not the range to which the router is set. All was fine when I manually entered an IP address within the proper range.
Since the other network devices seemed to work, I assumed the problem was with the Chromebox, so I factory-reset it. That did not solve the problem. I then installed a brand new network device, and discovered that it, too, received the wrong IP address.
This morning, I replaced the router. To my surprise, the problem persists. I now have three network devices that receive the wrong IP address and gateway IP. On two of them, I set the IP address manually. But the third device is a Nexus 5 running Android Marshmallow. It apparently has a bug that doesn't let me set a static address.
Any ideas about why the router is either providing the wrong address, or why some devices are misinterpreting?