(Have Comcast gigabit service), Max speed I get hardwired ever was 800+. Usually hovers around 600. Have to reboot every day or two, otherwise download speed drops to 50mbps, upload speed remains constant at 42mbps. Rebooting modem "fixes" issue. The speed dropping and having to do a reboot to fix it is my issue. Got a new modem in december compatible with new gigabit service. Old modem with 300mbs service was rock solid.
The signal stats looked o/k at that snapshot in time. Are there any error log entries being shown ? If so, please post them in their entirety.
What is the exact make and model number of the modem ?
After I rebooted early this morning when it was 80mbps, it went to 700-800
Few hours later now:
Xfinity.speedtest. com showing 380mbps on 1Gig connection
Speedtest.net peaks at 600mbps then drops to 360mpbs at end of test
uploads on both are steady at 42mbps
Modem is Motorola MB8600 docsis 3.1 (installed earlier this year) and speeds were consistently around 800+mbps, occassionally going to 900.
Here is event log
Even though the signal stats looked o/k at that snapshot in time, the error log entries confirm that something is going on. Perhaps there is noise ingress into the line(s) somewhere.
There are other signal stat figures that can't be read by the modem. They are the "Upstream Rx Power" (Upstream Receive Power Level), the "Upstream SNR Ch." (Upstream Signal To Noise Ratio), and the "Upstream ICFR" (In Channel Frequency Response). These are as equally important in diagnosing connectivity issues as are the modem's stats.
I'm going to escalate your issue to the Comcast corporate employees that are available to these boards. They can check the CMTS (Cable Modem Termination System) for any real time degradation and / or error reports, see your node / cable plant and modem health, and see whether or not everything is in the green zone. They can also see a history plot for the modem and poll for those upstream receive signal stats.
You should get a reply here in your topic. Good luck !
Thanks for your help. I had 300mbps with surfboard modem and had no issues. Only reason I wen to Gigabit was because it was $10 cheaper since I went off 1yr 300mpbs contract. I have not had any issues with Comcast except for the occassional outage.
Quite welcome !