10 years of Intermittent Connection problems

@XfinityMartyR​ Yes, I've reviewed this post before. Over the past ten years, I literally tried every relevant option listed on that post and more not mentioned there specifically.

As I previously said, I have had the same connection problems using five different modems over that time. I've changed every ethernet cable I own multiple times as well. Something is 100% wrong with the coaxial cable connection coming into my apartment. I do not have any splitters in my home, I only have a single coaxial cable from my modem which is connected to a line coming out of the wall.

All of the error codes I've seen from all of my different modems are the same.

Netgear: 
(Critical (3))  UCD invalid or channel unusable;
(Critical (3))  Started Unicast Maintenance Ranging - No Response received - T3 time-out;
(Critical (3))  Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received;
(Critical (3))  No Ranging Response received - T3 time-out;
(Error (4))  DBC-ACK not received;

Arris:
3 UCD invalid or channel unusable;
3 Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;
3 Started Unicast Maintenance Ranging - No Response received -T3 time-out;
3 No Ranging Response received - T3 time-out;

There are other errors/warnings/notifications, but those listed above are the most common codes, and my modems have reported HUNDREDS of these just over the past two days. 

Every modem I've owned and used in this building has logged similar errors, and all of the research I've done points to an ingress problem coming from outside of my home.

Additionally, my upstream power levels are out of the recommended spec. On my Netgear CM2000 it's currently at 59dBmV. 

I was told by one technician back in 2021 that they were going to escalate this to whichever Xfinity department is in charge of running a new wire, but I never got a response. I had another technician come out within the last six months, and they recanted and said it's my equipment, which is provably NOT TRUE!

I truly do not know what to do and I've been paying for an nearly useless service for a long time. I'm a day or two away from canceling my Comcast service and moving to a competitor at this point.

It sounds like you've done a ton of troubleshooting for us already and we can always take a look to see what can be done. Could you private message me your full name and address? 

I'm trying to message you, but your name doesn't show up on the PM list. Any help?

To send us a direct chat message @InfiniteFrustration, please click on the chat icon located at the top right of this forums page.

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Thank you for the help.