Wired Network Speeds

Have been experiencing network speed issues for roughly the last 3 weeks on Wired connections. The household has roughly, on average, 8 to 11 devices connected to WiFi at a time with generally only 3 devices on wired connection. Ports on the XB8-T are constantly flashing orange and from ethernet connection I am receiving no more than 80Mb/s on average while wireless connection I am getting up to 800Mb/s. 

I have had 1GB speeds for the last 8 years or so and haven't had any issues, 7 and a half of those years were on my personal modem/router combo and the past month I moved over to using Xfinity's Gateway (which is the XB8-T that I mentioned earlier) for the last 4 months roughly. 

Both speedtest connections were from Speedtest.net and both sent to San Jose.

Any advice or additional troubleshooting tips appreciated. I've swapped out the XB8-T recently and still getting the same issues,received new coaxial cables and still the same.
I've used multiple Cat5e cables ever since the issue first started and am ordering a cat6 just to test but I doubt it'll make any changes.
I have not made any New changes to admin gateway since the issue so I can't think of anything that would've started this to occur.