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Cm1200 Modem dropping connection. Unstable intermittent internet


Cm1200 Modem dropping connection. Unstable intermittent internet

As the title states that is the problem. Xfinity is trying to tell me its my modem is bad. I suspect it is old cable lines that are making “ noise” in the line causing the poor connection. I was chatting with them the other day and they said they were going to restart my modem.They tried to restart it but said they could not find it and it must be offline. But i was streaming netflixxthe whole time, so how could gave it been offline. A while back the tech was here because of the same problem. There was a splitter in the line. And he discovered one of the lines off the split ( was not being used) was causing noise in the line. So he bypassed the line and connected the one main line together. It was fine for awhile but now back to same problem. some times the connection runs fine but then it will start crapping out. The other day i noticed the upstream light was flashing on the modem and it also turned red/orange at one point. Posting a photo of most current event log. Not sure how to create a file to get the full log here. Hope the recent is enough. Thanks for any anticipated help and insight
Message 1 of 5

Re: Cm1200 Modem dropping connection. Unstable intermittent internet

Cable connections page pr 1
Message 2 of 5

Re: Cm1200 Modem dropping connection. Unstable intermittent internet

Cable connections page part 2
Message 3 of 5

Re: Cm1200 Modem dropping connection. Unstable intermittent internet

You have lots of criticals and some errors that the ISP needs to review and help resolve. 



Be sure your using a good quality LAN cable between the modem and router. CAT6 is recommended. 
What is the brand and model of the host wifi router connected to the modem?


Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly.
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. 
Start with removing any amplifiers, signal attenuators, or splitters from the coax.
From there check the line for kinks, damage, moisture in the line.
Check the connectors for improperly made ends, foil touching the copper coax line, loose connections, bad/old/cheap connectors, or corroded connections. Replace them if you do.
Be sure to power OFF the modem for 1 minute then back ON.


Can try a different modem to see if the problem continues or not.

My Setup ISP SparkLight | Internet Cable 1000↓/50↑ CAX30 Mode Mode  | Wifi Router XR500 and RBK863 Router mode | Switches NG GS105/8, GS308v3, GS110MX and XS505M | Additional NG HW: C7800/CAX3/CAX80/CM1100/CM1200/CM2000, Orbi: CBK40, CBK752, RBK50, RBK853, RBK752, RBK953, SXK30 | NightHawk: MK63, R7000, R7800, R7960P, R8000, R8500, RAXE500, RAX120v2, RAX50v2, XR450/500/700/1000, EX7500/EX7700

Message 4 of 5

Re: Cm1200 Modem dropping connection. Unstable intermittent internet

Your logs indicate a line issue. 

But your cable connections page doesn't look to bad. A little out of spec on the power but not a ton. (supposed to be within 3.5dbmv of each other on the downstream channels).

Next time you run into the issue, then pull the cable connections page as it takes a snip of it when you open it up. When the upstream flasheds, its usually indicating that only 1 of the upstream channels is locked. Which will cause issues. But its also important to determine whats going on with the downstream at the same time the upstream is having issues. 

Current setup: CM2000-> RBKE963B-> Trendnet TEG-S380-> GS716T-> pi-hole
also in AP setup: RAXE500->EAX80
1.4gig download/50mbps upload from Xfinity
We’re members of the public helping out on our own time.
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