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Huger variance in performance flapping between 280 Mbps and 33 Mbps, any ideas?

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Huger variance in performance flapping between 280 Mbps and 33 Mbps, any ideas?

On 6/16, my cable modem died after 6 years of steady service; it consistently measured between 120-160 Mbps. I have been paying for up-to 250 Mbps but didn't care since it was fast enough and I didn't need full-speed.

 

The Xfinity support folks told me my modem it was unreachable and it was blinking red on uplink. I purchased a docsis3.1 compatible motorola modem and had it activated. It was functional but it bounced dramatically between 32 Mbps and upwards of 280 Mbps. It was basically flapping between full-speed and minimum speed.

 

I went to an Xfinity store and described the problem. I was told that Arris is the model Xfinity provides, so I bought that and activated that. Well - same problem. This is fairly compelling evidence that the issue has nothing to do with the modem.

 

My performance will measure 280 Mbps one minute, and then 33 Mbps the next minute. This is occuring when I am directly connected to the modem via ethernet - NOT over wifi. So, I know the issue is on xfinitiy network-side not on my home network.

 

Given the slow flap is ALWAYS 33 Mbps, not some random lower value it seems to me that there is some provisioning or perhaps IP-network configation problem on the xfinitiy side.

 

Anyone have any ideas as to why I would bounce between 33 Mbps and 280Mbps? They change slightly (maybe +/- 10 mbps) but it definately seems to be flapping between MAX and MIN throughput.

 

Any ideas?

Frequent Visitor

Re: Huger variance in performance flapping between 280 Mbps and 33 Mbps, any ideas?

It's not your modem. They always say that. Check your signal to start with. I think you'll find it's poor.

 

You can find instructions and other trouble shooting tips here: https://forums.xfinity.com/t5/Your-Home-Network/Xfinity-Internet-Connection-Troubleshooting-Tips/m-p...

 I'm not a tech so I don't know if any of the info here is dated now, but it will still get you in the right direction.  Also there's a pinned post detailing what info peopl here will want in order to help you diagnose. I missed it the first time I checked in here.

 

It's a good idea to make sure it's nothing simple like a loose connector to be sure, but the problem has never been on my end.  Cable junction splitters are also a sore spot.  Even If the signal incoming to your location was preiviously adequate, if it degrades for some reason and junction can mean that the signal is now too weak once split up.

I frequently have very similar issues to yours, as do others. Xfinity is not very forthcoming as to why this happens.

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Expert

Re: Huger variance in performance flapping between 280 Mbps and 33 Mbps, any ideas?


@sausageboss wrote:

My performance will measure 280 Mbps one minute, and then 33 Mbps the next minute. This is occuring when I am directly connected to the modem via ethernet - NOT over wifi. So, I know the issue is on xfinitiy network-side not on my home network.

Are you sure?

When you do this, is your test computer the only device connected to the modem? Have you turned off security apps and other programs that might be eating at your bandwidth while the test is being done? What's the model of your modem/gateway? 

 

You can look at Xfinity Internet Connection Troubleshooting Tips  and Information Requested for Connection-Related Posts for ideas. 

 


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Official Employee

Re: Huger variance in performance flapping between 280 Mbps and 33 Mbps, any ideas?

Hello, sausageboss! Welcome to the Xfinity Forums. 

It has been some time since we heard from you and I wanted to check and see if you were able to stabilize your connection using the help that blackwk and darkangelic provided? I look forward to your update so I can help if you are still having troubles.


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Official Employee

Re: Huger variance in performance flapping between 280 Mbps and 33 Mbps, any ideas?

As there have been no new responses here in quite some time, I have closed this thread to further comments. If anyone here is still in need of assistance, please feel free to start a new thread. 


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