Router (CGM4140COM) not properly negotiating 1000mbps link speeds with Ethernet connected devices.

Devices seem to keep negotiating 100mbps link speeds when they are gigabit capable. Problem only started to occur for the past month or so.

Current fix is to just replug/restart the networked devices until it properly negotiates to gigabit link speeds.

Have one device hardwired with a CAT6 cable, and two others via a switch (Tenda SG105)