cm1000 power levels

[cc22]

Hello, I've been having issues with my Internet since switching to gigabit with Xfinity in May of 2019. I recently switched from an Arris SB8200 to the CM1000 and saw an almost immediate improvement. After a week or so the problems came back and I was back to only getting 34.2mbps both over the router (Linksys EA9500V2) and hardwired through the modem. Xfinity is supposed to be replacing all of the cable lines as they are a combo of 12 year old DirecTV cables and ancient 80's cable. I've been keeping an eye on event logs and I have multiple T3 and T4 timeouts throughout the day, but power levels are in the -7 to +7 range. Today they all range from -6.9 to -12. What should I do now? Would replacing the cable help this? Should I look to replace the modem? Outlet? Thanks in advance.

[plemans · Accepted solution]

You've got a lot of errors in your line. Something to keep in mind is that the cable connections page is a snap shot at the time you accessed it. The power levels can vary a bit. They should be withing 3.5dbmv of each other. You've got  a range from -6.9 to -12. so roughly 5.1dbmv range.

What I'd do? move the modem (temporarily) to right where the coax enters the home. Then run the same test and repost back here. If the levels are good, its something within the home such as wiring/connector/etc. If the levels still aren't decent, then xfinity needs to look at the wiring external to the home.  

[cc22]

Here are the timeouts.

[plemans · Accepted solution]

You've got a lot of errors in your line. Something to keep in mind is that the cable connections page is a snap shot at the time you accessed it. The power levels can vary a bit. They should be withing 3.5dbmv of each other. You've got  a range from -6.9 to -12. so roughly 5.1dbmv range.

What I'd do? move the modem (temporarily) to right where the coax enters the home. Then run the same test and repost back here. If the levels are good, its something within the home such as wiring/connector/etc. If the levels still aren't decent, then xfinity needs to look at the wiring external to the home.  

[cc22]

After moving the modem, the power levels changed as shown ranging from 0.6 to 5.1 bringing it closer to the 3.5 but still not there. Upstream dBmV 46.3, 47.0, 47.3. 

[plemans]

No errors so far. Watch it for a bit and see how the errors do. Power levels much better

[cc22]

No more error messages so far. This seems to have fixed it. I extended the line to get the modem where it needs to be for now until Comcast can get out here to run the new cables. Power from -1.7 to 3.6! Nothing showing in the event log! Thank you so much!

[plemans]

Glad to see its working better!

Not sure about your area but in my area, comcasts charges to run cables within the home. Exterior to the home, they don't. something to keep in mind is that if the problem is the wiring in the home and they're going to charge you $75 to fix it, it might be cheaper to try replacing some coax ends (usually whats bad), check for kinks, replace splitters/etc.