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I upgraded to DOCSIS 3.1 and Gigablast, and, instead of getting better, my connection is so slow I am getting kicked from online video games, and videos I upload, do not complete because of disconnects during upload. Cox please fix your lines/software. This has been happening for 11 years. Your technicians are incompetent and arrogant so I refuse to have them in my home ever again.
Could be noise at 300Mhz, or your OFDM channel. Have you tried a direct connection to the demarc?
Check out these articles that confirm the OP’s sentiment.
docsis/gigablast “upgrade” messaging from Cox:
I got the same email and info. I upgraded to a 3.1 modem but was still getting emails telling me that I had to upgrade the acct. I upload videos to YouTube so the upload speed is really nice to have.I thought $15 more a month for gigablast, sure why not. Right now my DL speed is 100 Mbps slower than before.
This is a scam by Cox. I called the number and the rep confirmed this was nothing but a poly to get people off the old 300/30 plan. I'm filing a complaint with the OKAG and advise anyone else impacted to do so. There is no "technical/Network upgrade" Cox is doing to require a change like this. This is their way to get people to either A. upgrade equipment or B. upgrade plans so that they do not have to Grandfather us in. The 500mbps they are offering if you do not change your modem is a joke, as A. you'll still be capped at 300mbps down, and B. your upload speed is being DOWNGRADED to 10mbps