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What happened to my download speeds?

Teacher2020
Frequent Visitor

What happened to my download speeds?

A little over a week ago I upgraded to Gigabit level. I bought an Arris SB8200, activated and was getting over 900 down and 40 up after a technician came out and ran a brand new line outside. Super!

 

Suddenly yesterday I was getting NINE down and up. What?

 

Got support online today. Long story short, I am now at 100 down and I'm back to 40 up. What is going on? Nothing has changed on my end since the upgrade. 100 down is just not acceptable. But what worries me more is how this could happen out of the blue. Two teachers in this house that need to use Zoom all day.

BruceW
Gold Problem Solver

Re: What happened to my download speeds?

Are you connecting via Wifi or Ethernet? If Wifi, it's best to switch to an Ethernet cable connection if possible. That would allow you to determine whether the problem is the Wifi signal or the link between your equipment and Comcast's network. Network connection problems that affect both Ethernet and Wifi devices are often due to poor coax connections or damaged coax cable, usually in or near your home.

If you want to troubleshoot this yourself, please see Internet Troubleshooting Tips. If you still need help, please post your modem or gateway's model number and signal information, especially downstream power levels and SNR, upstream power levels, and error log.

If you can't find the problem or you'd rather have Comcast take care of it, call them at the phone number on your bill or 1-800-Comcast, or use one of the options on https://www.xfinity.com/support/contact-us/. If they can't fix the problem remotely (unlikely), insist they send a tech out to identify the cause and correct it.

If the tech finds bad coax, splitters, amplifiers, or connections in your home (even if Comcast originally supplied them) you'll probably have to pay for the visit unless you have their Service Protection Plan (https://www.xfinity.com/support/articles/service-protection-plan, closed to customers that don't already have it). If the trouble is due to a faulty Comcast rental device, or anything outside your home, you shouldn't be charged.

Teacher2020
Frequent Visitor

Re: What happened to my download speeds?

Thank you Bruce, I have done speed tests directly from the SB8200 connected to my computer via Ethernet, bypassing my Eero router just to be certain. Router definitely not the issue.

 

I will upload the error logs. What I don't get is why would I have blazing speeds and then all of a sudden 100? Something like that isn't going to be caused by a splitter imo. Not when it was working perfectly fine just days ago.

Teacher2020
Frequent Visitor

Re: What happened to my download speeds?

Teacher2020
Frequent Visitor

Re: What happened to my download speeds?

BruceW
Gold Problem Solver

Re: What happened to my download speeds?


@Teacher2020 wrote: Here is the status page ... Event log ...

Several downstream channel levels are borderline/out of spec (too low), and channel 37 also has a very high uncorrectable error count. The event log entries point to a problem with this channels as well. If the troubleshooting tips link previously posted doesn't help you to correct this, I'd recommend having a premise tech out to clear up the problem.

steagallcraig
Frequent Visitor

Re: What happened to my download speeds?

I am in the same boat as you. I have the same modem and the same thing happened to me. I had the 300mb plan, got this modem and was somehow getting 950mb. Being honest, I called and said I wanted the 1GB plan. As soon as i changed it dropped to under 500. Most days its 300-400. If i am lukcy I can get 500 for an hour or so. A tech came out and changed the line to my house. Then a line tech came out and supposedly changed out the box on the line. That changed nothing. My logs look almost identical to yours, but my power on the up is on 31-32. So frustrating. 

EG
Expert

Re: What happened to my download speeds?


@BruceW wrote:


and channel 37 also has a very high uncorrectable error count. The event log entries point to a problem with this channels as well. If the troubleshooting tips link previously posted doesn't help you to correct this, I'd recommend having a premise tech out to clear up the problem.

FWIW BruceW, channel 37 is the OFDM / "other" channel and that's the known measuring mechanism glitch issue.

 



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Teacher2020
Frequent Visitor

Re: What happened to my download speeds?

Yeah I just don't understand why it worked wonderfully for a week and then suddenly download speed fell off a cliff.

steagallcraig
Frequent Visitor

Re: What happened to my download speeds?

Look familiar?
Screenshot_20200915-193521_Chrome.jpg
Screenshot_20200915-193555_Chrome.jpg
BruceW
Gold Problem Solver

Re: What happened to my download speeds?


@Teacher2020 wrote: Yeah I just don't understand why it worked wonderfully for a week and then suddenly download speed fell off a cliff.

Bottom line: If you can't find the problem, the only thing left to do is to lean on Comcast until they diagnose and fix it.

Teacher2020
Frequent Visitor

Re: What happened to my download speeds?

Worked with another online tech today. She said that the signal numbers reported were within spec and maybe the modem was the problem. Could have a tech come out but due to COVID, literally no idea when. I said that I could not continue to deal with sub-100 download so perhaps we should re-activate my old Arris SB6183. So we did.

 

550 down, 6 up. The 6 up is exactly why I contacted them in the first place, when they suggested I upgrade to Gigabit speed. She said someone higher up would call me in the coming days.

 

In the meantime I decided to exchange the SB8200 so at least I'll be taking the "bad new modem"  possibility out of the equation.

 

In review to this point: SB6183 (DOCSIS 3) I get 550 down and 6 up. With the SB8200 (DOCSIS 3.1) I get 97 down and 40 up. Pick your poison.

BruceW
Gold Problem Solver

Re: What happened to my download speeds?


@Teacher2020 wrote: ... I said that I could not continue to deal with sub-100 download so perhaps we should re-activate my old Arris SB6183. So we did. ...

Note that Comcast's https://www.xfinity.com/support/devices page for the SB6183 says "Wired Download Speed Up to 373 Mbps", so if you're paying for an Internet plan faster than that, you're not getting your money's worth. Although if the configuration you have now is working for you and it's stable, you may well prefer not to mess with it further.   😉

Teacher2020
Frequent Visitor

Re: What happened to my download speeds?

This morning I thought I would try the Comcast Cares Twitter direct message. Had a good experience. They activated the new SB8200 and I am back to the speeds I had when I first upgraded two weeks ago (over 900 down and 40 up). Now to see if it holds.... 🤞 

 

FYI for those of you who use Twitter...although there is a team on their account that switches off, you have the advantage of one thread when you use Twitter DM. Good to have that saved dialog in my opinion. Also very easy to upload pics of settings, speeds etc. I think I will just stick to that method going forward.

Calamityjane12
New Poster

Re: What happened to my download speeds?

I’m having the same issues and I actually have their SB7 router. It makes no sense whatsoever. They’ve actually replaced the router, taken the line off a splitter that wasn’t necessary and re-set it God knows how many times. It’s just not consistent or reliable.