Yep--me too! Add me to this list. Comcast techs have been to my house twice. First one claimed that problem was my older Arris 6120. I had removed all my connected switches at this point, and my WIFI router, and also re-terminated ethernet connections and tested them. So, after big Xfi gateway installed by tech, I saw speeds I had never seen before for my 275Mbps Download service. All was great for just over 24 hours until about 8:30 pm the following night when I had one device connected via ethernet on a video call. Call connection dropped multiple times over ethernet. Speed test reported 2.1 Mbps download over ethernet! Often I see very low download speed with higher upload. So, there is NO way that my entire wiring, swithes, etc. suddenly failed at same time. Power reset takes a long time with xFi gateway, and didn't improve speed the last time. My contract ends in January, so I will be looking for a new Internet provider. In the meantime, complaints of low speeds below contracted agreement, can be sent to the FCC and FTC. Maybe this will encourage Comcast to fix this. During the video call, the person on the call in Ukraine reported a better connection than mine! Nuff said!
Correction: I started seeing these extreme fluctuations over Internet a few months ago on a network that hasn't been changed or touched in years!
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