6 Messages
Speed less than half of advertised on MB8600
Hi!
I recently moved into a new rental and installed a brand new MB8600 (DOCSIS 3.1) with the 800 Mbps plan.
Even directly connected to the modem over Ethernet I basically never see anything more than 400 Mbps. Speed tests typically come in around 100-200 Mbps, sometimes less.
The house used to have a 5-way splitter leading to each room, and sometimes the modem wouldn't even connect at all. I removed that and installed a new amplifier splitter instead. The modem now connects reliably, but the speeds are terrible. I also use MoCA devices in the house to connect different rooms, but I have consistent speed variability and issues even when no MoCA devices are connected.
It is an older house and I am wondering if the coax is bad. Attached is the connection information from the modem, but I don't know how to interpret it. Can someone help take a look to see if this might suggest bad wiring in the house, or some other issue?
Thanks!
Accepted Solution
BruceW
Gold Problem Solver
•
26.2K Messages
1 year ago
There's really no way to tell from a distance, but you do have serious signal problems. Two downstream channels are not locked, four more show "Locked", but have 0 SNR, a few others have SNR that is non-zero but still out of spec (too low), and a number of channels have very high uncorrected error counts. Meanwhile all the upstream channel power levels are out of spec (too high).
Network connection problems like this are often due to poor coax connections or damaged coax cable, usually in or near your home. Running the cable through a surge protector, a defective splitter, or too many splitters can cause signal problems as well. OTOH the problem could be at the pedestal or tap, or even farther upstream,
If you want to troubleshoot this yourself, please see Internet Troubleshooting Tips. If you can't find the problem or you'd rather have Comcast take care of it and an employee does not respond to your message here, 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/. It's not likely they can fix the problem remotely. If not, 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 (approx $100) 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.
Please be aware that there are 2 kinds of responses in this Forum: Replies and Comments. When you Comment on a post by scrolling down to "Comment on this post here...", I am notified of your response. But if you select Reply, I am NOT notified and may not be aware of your response.
(edited)
0
XfinityAlfonso
Official Employee
•
1.3K Messages
1 year ago
Hey there @user_ci thanks o much for this full context and even the screenshot showing the full connection issues. We'd be more than happy to help get a tech out there to see what's going on.
Please send a direct message by clicking the chat icon in the upper right corner of the page, click on the pen and paper icon, then enter “Xfinity Support” in the “To” section. Please include your name and address and I'll be happy to help.
0