Before I factory reset the thing has anyone hit this issue?

Two separate devices can't get an IP using any of the physical LAN ports. It appears to be connected on the router (ports lit up) but the router doesn't assign IP's nor allow fixed IP connections.Windows is just sitting there going 'identifying network' before giving up and defaulting to a 169.x.x.x address.

Everything was working fine up until the last half hour with no network changes. So far I've rebooted the router and done a bunch of things to the Windows PC's NIC (which I suspect isn't the problem as it's now got the latest drivers etc, and it's occurring on another device). Wifi works fine.