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Very slow internet, please help!

Frequent Visitor

Very slow internet, please help!

Hello. We have been having problems with our Xfinity internet. We’re paying for 150mbps down/ approximately 15mbps up. When it works properly, we see 180mbps down 15mbps up. Lately we’ve been seeing only 1.5 to 20mbps download. Upload is unaffected. There is no rhyme or reason to the speeds changing. Sometimes it’s blazing fast during the day, other times not, sometimes it’s fast at night, etc. We’ve done all the power off/check cables and tighten routine etc...We’ve had techs out and had all splitters and coax cable replaced in our home. We only have two splitters in our setup, and the cable modem is connected to the first splitter which splits directly from the line coming into the house.

We decided to upgrade to a new modem in case that was our problem. We had an Arris SB6141, and upgraded to an Arris SB6190. Same problem.

Techs have analyzed line signal strength and said we’re ok. When I look at our downstream signal strength in the modem status page, they’re all around the low -20dBmV level. Only a few are around -15dBmV. We only get 7 of 32 channels bonded for download.

I read some things about MoCA filters that can cause internet problems, so I tried swapping out the filter in the box on our house with a standard splitter. This caused our internet to shoot up to 105mbps download immediately, but without the MoCA filter, our X1 TV service doesn’t work. Put the filter back, TV works, but the internet speeds drop drastically again.

We have a signal amplifier coming from Amazon tomorrow, but I figured I’d ask here and see what the general opinion is. Bad filter? Weak signal?

I’ve got a screenshot of the modem signal strengths if needed.

Thanks

Mike
Frequent Visitor

Re: Very slow internet, please help!

Here’s a screenshot of our modem signal levels, taken just now:

https://ibb.co/D4K5gGR
Expert

Re: Very slow internet, please help!

Nope. Whatever reps that you talked to were wrong. Phone reps are NOT techs !! That downstream power is way out of spec !! Yeah. A weak signal ! And an amp may not help because the SNR is also low / out of spec. Garbage in equals garbage out ! You should get a tech out to actually do a boots on the ground investigation of your line.


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Frequent Visitor

Re: Very slow internet, please help!

Thanks for your reply. Yeah the downstream looks pretty bad. It was a tech we had at the house awhile back who said our signal was good as measured at the drop on our house! Maybe something has changed since then.
Official Employee

Re: Very slow internet, please help!

Hello, five28ia! I'm so glad you reached out to us for assistance!

I would like to work with you to get a tech scheduled for repairs and monitor the situation so I can make sure we get this fixed so you can enjoy reliable service once again. Please send me a private message with your first and last name so I can assist. 

 

 To send a private message, click my name "ComcastTambrey", then click "send a message".


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Frequent Visitor

Re: Very slow internet, please help!

Thanks for your offer of help, but we called out a tech already before I saw your reply to this post. Kinda hard to use the net at 0.41 mbps download lol.

We tried an amplifier, which kinda worked but mostly didn’t. Modem was having constant disconnects. Need a good signal in to boost otherwise you’re not gonna have good results.

Our internet is fixed though and back to blazing fast!! The tech replaced the line from the pole to our home. It was probably the original coax line, almost 40 years old. Tech said it seemed like there was water in the line, and it was coming apart in some areas.

Here’s the modem status page. We’ve got all 32 channels bonded and all are right around -3dBmV to 0! 180mbps down rock solid. Thanks to everyone who replied Smiley Happy
9D2EB587-1349-4333-9297-E04B9184BAC1.jpeg
Official Employee

Re: Very slow internet, please help!

@five28ia, thanks for reaching back out and providing us with this update! I am delighted to hear the tech was able to determine the problem and get it resolved for you. I truly apologize for any inconvenience or frustration this may have caused as well. Please be sure to reach back out to us for any future issues or concerns, we're here to help. Thank you and we appreciate you being the best part of Comcast. 


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