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Multiple modem errors

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Regular Visitor

Multiple modem errors

Hello. I’ve been having serious internet issues, most of the time I’m getting a speed of less than one Mbps, I used to get 200+. I’ve got a netgear nighthawk modem and an eero pro mesh WiFi system, so nothings outdated. I called Comcast and they said it’s probably an issue with the modem, but im almost positive it’s an issue with the outside. I’m getting several “Started Unicast maintenance ranging - No response received” and “No ranging response received” errors according to my modem. All the proper lights are on but somethings just not right. Rebooting the modem fixes the issue for around 15 minutes, then it goes right back. Can someone please, please help me?
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Expert

Re: Multiple modem errors

What do the modem's signal stats look like ? Try getting them here; http://192.168.100.1

Please post the *Downstream Power Level*, the *Upstream Power Level*, and the *SNR* (Signal to Noise Ratio) numbers.




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Regular Visitor

Re: Multiple modem errors

Right. The downstream power level is hovering around -3.0 for every bonded channel, and the upstream power level is 48 for each. The SNR ratio is 45 on all the downstream channels. I’m also receiving “ DBC-REQ Mismatch Between Calculated Value for P1.6hi Compared to CCAP Provided Value;CM-MAC=28:80:88:d1:5e:30;CMTS-MAC=00:90:f0:1a:00:00;CM-QOS=1.1;CM-VER=3.1;” quite a lot.
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Expert

Re: Multiple modem errors

The upstream power is on the high side and it may be intermittently fluctuating even higher to out of spec levels. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the un-bonding of channels.

In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.



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We ask that you post publicly so people with similar questions may benefit from the conversation.
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