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Download speeds are great, upload speeds are spiking/fluctuating

Posted by
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Member Since: ‎10-28-2012
Posts: 10
Message 1 of 14 (3,158 Views)

Download speeds are great, upload speeds are spiking/fluctuating

My download speeds during speed tests stay at a constant 52Mbps.  While my upload speeds sometimes will stay at a consistent 9-10Mbps for a couple of minutes, it usually is hovering around 4-7Mbps, which seems like great numbers, but in the middle of that it will drop to like .1 - .4 Mbps.

 

It's super noticeable when trying to watch videos, download things, and especially game.  In most P2P games, I get host 99% of the time, now I don't get host, and while playing the games, it's incredibly unbearable to play, I skip around, warping all over the maps, can't play at all.  While in Ventrilo with my buddies, it takes about 30-45 seconds for what I said to go through and for them to hear me, and my vent ping is constantly spiking between 20ms and 11000ms.

 

This just started happening Thursday.  I've called Comcast and they've "refreshed" my line and a bunch of other stuff on the modem/router.  They're scheduled to have someone come out on Thursday morning, but I figured I'd post and see if anyone has any ideas/suggestions as to why it's acting this way?

 

Thanks.

13 REPLIES
Posted by
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Member Since: ‎10-28-2012
Posts: 10
Message 2 of 14 (3,157 Views)

Re: Download speeds are great, upload speeds are spiking/fluctuating

I forgot to add this in the OP.  This happens all times of the day, during peak hours and dead hours.

Posted by
Cable Expert

Member Since: ‎06-27-2009
Posts: 13,222
Message 3 of 14 (3,116 Views)

Re: Download speeds are great, upload speeds are spiking/fluctuating

We need more information please:

- Post your upstream and downstream signal levels. Click the link or type: http://192.168.100.1 into your browser. We are interested in your power levels (dBmV) and your Signal to Noise Ratio (SNR). You may also want to contact Comcast and ask for your upstream SNR (uSNR) and receive level.
- Post your modem’s error logs.
- Post the make and model of your modem.
- Post the make and model of your router if you have one.
- Let us know if you contacted Comcast or had a tech visit.
- Let us know what the lights on your modem are doing when you are having problems.

- Plug directly into the modem (no router) via ethernet and run ShaperProbe.

 

Posted by
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Member Since: ‎10-28-2012
Posts: 10
Message 4 of 14 (3,113 Views)

Re: Download speeds are great, upload speeds are spiking/fluctuating

Thanks for the response.  When I get home I will post all the requested information.

Posted by
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Member Since: ‎10-28-2012
Posts: 10
Message 5 of 14 (3,087 Views)

Re: Download speeds are great, upload speeds are spiking/fluctuating

-My modem/router model is SMCD3GNV

-I have called Comcast and they have "refreshed" and "updated" the line, had me restore defaults to the modem/router, no techs have been here yet

-My modem/router's gateway IP is 10.0.0.1

-I have a modem/router combo so I'm unable to connect directly into the modem without the router

-This problem started around Thursday 10/25 or Friday 10/26

-The lights don't do anything different while the problem is occuring, they function as normal

 

CMS LOC Cleared	2012/10/27 23:20:28	Warning
MTA HW/SW Failure Cleared	2012/10/27 23:20:28	Warning
CMS LOC Cleared	2012/10/27 22:30:28	Warning
MTA HW/SW Failure Cleared	2012/10/27 22:30:28	Warning
CMS LOC Cleared	2012/10/27 21:40:28	Warning
MTA HW/SW Failure Cleared	2012/10/27 21:40:28	Warning
CMS LOC Cleared	2012/10/27 20:50:27	Warning
MTA HW/SW Failure Cleared	2012/10/27 20:50:27	Warning
::ffff:10.0.0.2 admin Login Success	2012/10/27 20:50:11	Warning

 

Posted by
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Member Since: ‎10-28-2012
Posts: 10
Message 6 of 14 (3,084 Views)

Re: Download speeds are great, upload speeds are spiking/fluctuating

Posted by
Cable Expert

Member Since: ‎06-27-2009
Posts: 13,222
Message 7 of 14 (3,058 Views)

Re: Download speeds are great, upload speeds are spiking/fluctuating

Your upstream levels are too high, they could easily be fluctuating enough to knock you off line. Try grabbing another set of signal levels as soon as you can the next time you are having issues. Pls post.

Posted by
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Member Since: ‎10-28-2012
Posts: 10
Message 8 of 14 (3,049 Views)

Re: Download speeds are great, upload speeds are spiking/fluctuating

http://i46.tinypic.com/13z788o.jpg

 

There are my upstream levels from just now, and I was in a game and having issues.  It's very intermittent, sometimes it will happen for 2 minutes straight, some times it won't happen for an hour, sometimes it will happen every 30 seconds, etc, it seems to be completely random.  There's definitely an issue somewhere though as my pings will fluctuate between 10-20ms and 9000-14000, and it wasn't always doing this.

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Member Since: ‎10-28-2012
Posts: 10
Message 9 of 14 (3,040 Views)

Re: Download speeds are great, upload speeds are spiking/fluctuating

http://i48.tinypic.com/2m7ue0i.jpg

 

Here's another one from just now where I was getting heavy lag/spiking.

 

Just an fyi, I am in an apartment and running multiple splitters - but I have never had this issue before last week.

Posted by
Cable Expert

Member Since: ‎06-27-2009
Posts: 13,222
Message 10 of 14 (3,009 Views)

Re: Download speeds are great, upload speeds are spiking/fluctuating

Can you run a traceroute to the game server? Follow the link in my signature if you need direction.

Posted by
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Member Since: ‎10-28-2012
Posts: 10
Message 11 of 14 (2,997 Views)

Re: Download speeds are great, upload speeds are spiking/fluctuating

Well I play a lot of MW3 and it's P2P, and Left4Dead2 and the servers are random, so it's servers from all over the United States/world.  I also experience the bad lag in WoW, but I can't seem to even ping the server.

Posted by
Cable Expert

Member Since: ‎06-27-2009
Posts: 13,222
Message 12 of 14 (2,962 Views)

Re: Download speeds are great, upload speeds are spiking/fluctuating

I don't think we can do much for you online. You should probably have a tech come out and check everything out. If he can't find a problem, he can refer the problem to the right department. If you get no joy, you might want to drop a note to Comcast corporate customer service (we_can_help@cable.comcast.com), they may be able to help you out.

Posted by
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Member Since: ‎10-28-2012
Posts: 10
Message 13 of 14 (2,902 Views)

Re: Download speeds are great, upload speeds are spiking/fluctuating

So the tech just came out and left.  He said he didn't see any power level problems, but he's seeing a decent amount of noise on the line and that it was probably coming from one of my neighbors equipment being that I live in a apartment.  He said he would let building maintenance know and they could back track it to where the noise was coming from.

 

Sound plausible?

Posted by
Cable Expert

Member Since: ‎06-27-2009
Posts: 13,222
Message 14 of 14 (2,899 Views)

Re: Download speeds are great, upload speeds are spiking/fluctuating

Yes, it sounds like he did the right thing. He should have referred it to Comcast's maintenance techs (the guys that work on the cable plant) so they could track the problem down. If you don't hear anything or see improvement in the next week, drop a note to the email address I posted.