Xfinity 1200Mbps /  35 Mbps Arris S33 Wired on 2.5Gbps Port - connected to a new Gaming Laptop with a 2.5Gbps port using a new Cat6 - speed test range from 500Mbps / 40Mbps to often only 300Mbps / 40Mbps. Xfinity came out and can’t figure it out. When they connect their own equipment to the coax direct their test show it’s a perfect connection and all signals and power levels are in perfect range…. Very frustrated, this is my second modem, my older one was working until it all of the sudden was no longer compatible with my plan (?) online support was also no help - I have spent hours trying to figure this out