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Tuesday, August 11th, 2026 8:42 PM

modem-to-CMTS instability/cable noise issues

Netgear Nighthawk Modem event log red flags: “SYNC Timing Synchronization failure,” “No Ranging Response — T3 time-out,” “Resetting the cable modem due to docsDevResetNow.” 

i have already gone through about two days worth of troubleshooting and getting my personal router/modem/home network set up in an effort to make sure these network connectivity drops are not in my end. Spoiler: they are not. My modem is having an issue staying in touch with Comcast’s ctms without drops. I can only surmise it has to do with a bad splitter/connector, or some kind of noise being introduced in the coax path. I request a tech to come out here and inspect building and local hardware, because that has to be the issue.

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8 hours ago

 

user_l07vd9 My team can further help you with getting a technician appointment scheduled since you been troubleshoting for the past two-days.

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