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New CM205V Interferes with TV Signal
When a CM2050V is connected to a three-way coax splitter (the modem, and two TVs to Xfinity Voice/Data/Cable television service, it disrupts the signal to the two tvs. Disconnect it, and the TVs are fine. Disconnect the standalone router, problem still exists. I rolled back to a Netgear C7100V in passthrough mode, and everything works again. The problem is definitely the modem. The only reason I bought this modem is because I received an email advising that Netgear will stop support for the C7100V on 7/31/25. Neither Comcast nor Netgear support can explain what's going on, much less make it work. Would be better to upgrade to CM2050V, but the C7100V will stay in place for now ANY ideas how to solve this problem? Thanks in advance.
Way too many correctable/uncorrectable errors for a 24 hour period of time.
DOCSIS 3.1 is backward compatible with DOCSIS 3.0. I do not think DOCSIS 3.1 is backward compatible with DOCSIS 2.0. If you are looking at DOCSIS 2.0 hardware, you want to check the coax type to ensure it is correct for the current DOCSIS 3.1 connections (RG6).
What were the upload/download throughputs with your new splitters in place?
You might find some ideas in chapter 3 of this reference: https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html
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Reluctant to publish the event log with the mac addressed, since they unique. Anything in particular you are looking for? Very much appreciate your time and effort.
Can remove the MAC address. However, Any Criticals, Errors or Warnings seen in the event logs needs to be reviewed and resolved by the ISP. Indicates a signal issue on the ISP line up to the modem.
Still need to see rest of cable connections page.
I have tried disconnecting one TV so incoming coax to split modem and 1 TV. I think that would be roughly the same? Didn't fix it. And remember, the C7100v has worked fine for at least 8 years. Here's some info from the modem when it was installed (and not working). Nobody knows with Downstream Status shows Poor, or whether that would make a difference. And, as you recall, the C7100V works fine. I'm thinking defective modem, but have no way to test or confirm. To put it back online involves activating again...
CM Status: Good
Downstream Status: Poor
Partial Service: Poor
Cable modem is in partial service mode. Your service provider might be under maintenance. Most of the time it won't affect your traffic and will automatically clear when work is complete.
Downstream Power Level: Good
Downstream SNR Level: Good
Upstream Status: Good
Upstream Power Level: Good
Please post the data on that same page that is down farther. Please scroll down.
Also include the Event logs page as well.
Wonder if its pulling more power or injecting.
whats recommended for modems/tv signals is to actually have a double splitter. You go incoming inline----->modem on one leg and then line out to tv/other splitters on the other.
Have you tried that?
Also, a screensnip of the cable connections page can help with checking power levels.
