CM500 - Very Low Upload Speed

[neals725]

Hello,

A few months ago, I installed the CM500 modem to go with the R7000 Nighthawk router I've had for a few months longer. We've had a lot of internet troubles, so we assumed it was our Xfinity internet plan (which wasn't the best anyway) was the issue. So we upgraded to a plan that gives us 300 Mbps download speed and 20 Mbps upload speed. We still experienced some issues, until I finally decided to check the upload speed, and it's nearly 0 Mbps. I've done quite a few speedtests, reset my modem and router multiple times, and made sure the firmware in both devices was up to date. I called Xfinity to see if they knew or could fix the issue, and they said to contact Netgear.

Speed Test Results:

Wireless:  264.7 Mbps down, 0.05 Mbps up
Wired to Router:  294.2 Mbps down, 0.12 Mbps up
Wired to Modem:  279.0 Mbps down, 0.08 Mbps up

Does anyone here know how I could fix this issue?

[FURRYe38]

Have the ISP check the signal and line quality UP to the modem. 
Be sure there are no coax cable line splitters in the between the modem and ISP service box. 
Be sure your using good quality RG6 coax cable up to the modem. 
Be sure to power OFF the modem for 1 minute them back ON.

[neals725]

Thanks for the answer.

I contacted the ISP earlier today. They checked the line quality to the modem, said it was fine, and then sent me over here. We do not have any line splitters, and I have rebooted the modem a few times.

As for the coax cable, how do I know if the one that I currently have is of good quality? It's a bit old, so I wouldn't doubt that as an issue.

[FURRYe38]

Try a different modem to see if the problem continues or not, if it does then the problem is either with the line or the ISP. If it doesn't, then the modem is the problem and may need to be replaced.