We have a G3100 router that no longer gives us the speeds appropriate for a gigabit internet plan. We have tried multiple ethernet cables, reboots, factory resets, unplugging the battery, and fiddling with settings on the router. Even a call with a technician today was not enough as minutes after the call ended, the 100 Mbps speeds returned. These measures will only temporarily give back the appropriate speeds and it takes anywhere from a few minutes to a few hours for the router to lose connection to the internet and then reboot to 100 Mbps for both down and up. While these speeds are slow, our internet connection is still stable with no other anomalies.
We are unsure if there is something wrong with the WAN port on the router and/or if there is something wrong with the ONT. The LAN ports on the G3100 work, but even setting the WAN to 1000 Mbps still results in the 100 Mbps speeds. We are hoping someone knowledgeable is able to guide us to a solution.