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Connection drops, no OFDM downstream channel lock

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Regular Visitor

Connection drops, no OFDM downstream channel lock

Spent over a week trying to get some help with this issue and feel like all I'm doing is banging my head against a wall. Just over a week ago Comcast came out to upgrade the equipment outside my home because fiber has been installed in my neighborhood. Prior to this appt my Netgear CM1200 worked smoothly, my downstream bonded channels had full service and one OFDM downstream channel locked as well. After the installation was complete, and ever since, my downstream channels now have partial service, and my downstream OFDM channel does not lock. Power levels also dropped drastically on downstream channels.

Called the tech supervisor who came back two days later and he added a second power amp inside the house, but no improvement. Next level crew came two days later. They rewired the power amp to run directly off the new fiber connection behind my house. They ran a new dedicated line from the main splitter inside my house directly to my modem. Downstream power levels were improved by this, but the terrible connectivity issues and the partial downstream bonded channels service, and no OFDM downstream channel lock issues remained.

Supoervisor then sent another tech out a couple of days ago who put another splitter in my attic that lowered my power levels again (still within specs though) and insists nothing is wrong with the line coming into the house or inside the house, must be my modem causing the issues. The modem is not even three months old, and it worked PERFECTLY prior to the fiber "upgrade" install. So what I'm told to believe is in that two hour window during which the first tech performed the install, with my modem not even attached to the line or powered on, it somehow developed an issue that is now the cause of my problem. I'm sorry, but that is an insanely difficult pill to swallow. 

Have spent hours with Netgear tech support walking through all of their troubleshooting and they conclude my modem is working and there is an issue with Comcast, somewhere up the line there is a problem.

So like many before me I'm in the Comcast says it's my modem, and Netgear says it's Comcast purgatory. So the tech supervisor tells me only other way to test is get one of their modems and see if the problems persist. But here's the rub - the 6 year old used piece of garbage Arris TG1682G they gave me is a DOCSIS 3.0 modem! This doesn't test my ACTUAL problem at all, which is their line not locking my OFDM downstream channel and causing horrendous connectivity issues. Of course the garbage modem I was given works, but that's not the point. My Netgear CM1200 is a Comcast approved compatible device. With it and my Netgear AC1900 router I had a STRONG, STABLE connection for EVERY single device in my home. Now, with this Arris POS if more than 3 devices connect to the wifi it starts dropping the signal.

At this point I've been told my only recourse is to go buy another brand new Netgear modem and connect it to see what happens. If I do so, and the issues persist, only then will I get additional investigation into my issues. This is beyond frustrating. I'm NOT a conspiracy guy like many around the web who say Comcast pushes you to use their equipment instead of your own, and a situation like mine where an upgrade in the area happens is a common time it occurs. But it's hard not to stray down that path.

At any rate, if anyone has any ideas or suggestions, I'm SO open to hear them. Thanks for reading.

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Diamond Problem Solver

Re: Connection drops, no OFDM downstream channel lock

If you don’t have gig service, the OFDM is a moot point. You didn’t post the speed tier you’re paying for or the signal levels, all important information. Continue working with your local contacts, using their gateway is just a form of troubleshooting

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Regular Visitor

Re: Connection drops, no OFDM downstream channel lock

Respectfully, using a DOCSIS 3.1 modem as opposed to a 3.0 can make a signifcant difference in the overall strength and stability of the signal inside my home. I am literally living the difference right now with this 6 year old Arris 3.0. It's not a moot point at all, and in the countless hours of research I've done in the last week all over, tech sites tell me exactly the opposite of what you said. I want to continue to work with Comcast, because I am nearly certain that there is an issue with my connection at the CMTS or somewhere up the line from my house that is causing the problem. But they aren't willnig. I begged the tech supoervisor, please come with a DOCSIS 3.1 modem and connect it and then show me it works perfectly and I will happily use the RMA I already have from Netgear to get a new modem. But he refuses says I have to buy my own new modem and test it myself and then they'll investigate further, but even then was like, there is not much else we can do. I literally had NO problems before the change over to the other connection, and now suddenly there is? The only change was what Comcast did. Listen, I'm not trying to be snarky, I am just at my wits end with being told I have a problem on my end when the only things different from when it worked perfectly is what they did.

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Official Employee

Re: Connection drops, no OFDM downstream channel lock

Hi, strikersfan. Thanks for posting here in the community. We would like to partner with you to see what we can do to help rectify the situation with your internet and the connection drops. I would be happy to either schedule a technician to have them come out and re-evaluate the premise another time (they would be able to identify whether or not it's an issue down the line beyond your premise) or see if we can get you a DOCSIS 3.1 modem modem to temporarily lease for troubleshooting purposes. You're welcome to send me a PM with your first and last name and I will get back to you as soon as possible. 

 

To send a private message, please click my name "ComcastMorgan" then select "Send a Message" on the right side.  


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