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Slow Upload Speed

Frequent Visitor

Slow Upload Speed

My upload speed was so bad on my 200/10, that I downgraded to 100/5. What's the point of paying for 10Mbps upload when all you get is 3Mbps???


I kept contacting support. They would make some changes, reset the modem, and my upload would be 10-12Mbps for a day or two. Then it would drop back down to less than 5Mbps. I'm on my second modem in 1 year because the last one had problems.


I hate living in an area where my only "fast" option for upload is 10Mbps, and the reliablility is just horrific.



Silver Problem Solver

Re: Slow Upload Speed

It's probably a signal problem, have a look at the troubleshooting here:

Post your downstream power levels / SNR and upstream power levels.

What make / model modem?

Frequent Visitor

Re: Slow Upload Speed

Sorry this took me so long to respond. I keep the modem in Bridge mode, so I had to find the time to do a hard reset. Here are the signal strengths and modem info:

Screen Shot 2017-07-24 at 12.21.56 PM.png



Screen Shot 2017-07-24 at 12.21.16 PM.png




The installer originally had to come out twice because the first amp that he installed was not strong enough. I just wish I could have better upload speeds. While slow upload speeds are ok for most, the slow upload speed coupled with poor QoS makes Skype calls impossible.

Frequent Visitor

Re: Slow Upload Speed

I solved my own problem. Hopefully this will help others.


If you have a Comcast provided signal AMP, do not use the VoIP (-4db) port for your cable modem!!!!!


Note my signal strength is much better now:

Screen Shot 2017-07-30 at 10.34.17 AM.png






Re: Slow Upload Speed

Just a FWIW, the only problem with that is that port on the amp is the one that will stay connected to the internet / phone service if there is a power outage to the amplifier (it's passive) and if you have a battery backup installed in the modem / gateway device.

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