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Forum Discussion
Modem CM1100
Hello,
In the last 3 days both times in the morning when I woke up the internet is out on the cable modem 2 days ago and this morning, I check with comcast and both times there is no outage in my area. I turned off and waited a minute or two and turned back on the works again. I've had this modem for months and no issue till these couple of days. Is this just a comcast thing maybe or could it be the modem. I checked and have the latest firmware. I looked at the event log and there were a lot of these 2 events showing: SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=6c:cd:d6:97:e3:9c;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1 and
Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=6c:cd:d6:97:e3:9c;CMTS-MAC=00:90:f0:04:00:00;CM-QOS=1.1;CM-VER=3.1.
I'm not a tech person, so not sure is this maybe why it happend and is this a modem issue or a comcast internet issue. Thanks for any help I can get.
Mike
1 Reply
What Firmware version is currently loaded?
Please post a copy and paste of the modems connection status and event log page.
https://kb.netgear.com/30007/How-do-I-obtain-the-cable-connection-information-from-a-NETGEAR-cable-modem-modem-router
https://kb.netgear.com/30008/How-do-I-view-or-clear-the-event-logs-on-my-NETGEAR-cable-modem-or-modem-routerBe 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.
https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Modems/m-p/1530376#M12853
https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router
https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html
