I have been getting T3/T4 timeout errors on my Netgear CM500 modem for over 3 weeks. Only temporary fix is to reset my modem several times a day. I called Xfinity and they scheduled a technician to come out. Technician came and tapped into our line right where it enters our house. He was unable to see any signal degradation up to the node on the utility pole or internal to my house to the modem. He suggested that the modem could have failed and I said I'd attempt to replace it.
Well, I purchased a new modem (same model, CM500) and registered it with Xfinity. Low and behold I get the same timeout errors. Xfinity has not proven the issues to be my fault or with something internal to my home. I am on the verge of cancelling service as I feel that I've been wrongly charged for a service technician to debug my issue. I am convinced the issue is with the connection up at the utility pole (node), which is something Xfinity is responsible for.
I used to be a Comcast/Xfinity customer about 7 years ago, then I switched to another DSL provider. Two years ago I switched back to Xfinity and I am regretting it. Oh, and I've been waiting almost 3.5 hours to get someone on the Xfinity chat to dispute the charges. I've been "number 1" in the queue for well over an hour... really???