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Forum Discussion
CM1000V2 and comcast, CM1000 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol
I've been battling disconnects, from 2-10 a day, packet loss, slow speeds. Playing World of Warcraft or Call of Duty becomes unplayable due to normal 50-60ms speeds going to 1100-2000ms+.
I've spent so many hours both online and telephone chat with Xfinity tech support. The last time a tech came out he replaced 85' of line from the pole to my home. It was ok for a couple days then right back to the same issues.
I've been keeping logs over the last few days. My time is off by 6 hours on the modem.
2022-10-19, 21:59:18 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 48; DSID: N/A;
2022-10-19, 21:59:08 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 48; DSID: N/A;
2022-10-19, 21:56:54 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 21:56:37 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 21:54:36 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 21:54:28 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 21:53:19 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 21:49:04 Notice (6) CM-STATUS message sent. Event Type Code: 4; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 21:48:33 Warning (5) MDD message timeout;CM
2022-10-19, 21:42:23 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 48; DSID: N/A; MAC Addr
2022-10-19, 21:42:19 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 48; DSID: N/A; MAC Addr: N/A
2022-10-19, 21:41:07 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 21:41:01 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 48; DSID: N/A; MAC Addr: N/A; ;
2022-10-19, 21:37:41 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 48; DSID: N/A; MAC Addr: N/A
2022-10-19, 21:37:30 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 21:35:16 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 21:35:04 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 21:31:53 Notice (6) CM-STATUS message sent. Event Type Code: 22; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 21:28:56 Notice (6) CM-STATUS message sent. Event Type Code: 20; Chan ID: 48; DSID: N/A; MAC Addr: N/A; ;
2022-10-19, 21:20:15 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 21:20:12 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 21:15:38 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 21:11:44 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 21:11:05 Notice (6) CM-STATUS message sent. Event Type Code: 24; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 20:58:52 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 20:58:32 Notice (6) CM-STATUS message sent. Event Type Code: 16; Chan ID: 48; DSID: N/A; MAC Addr: N/A;
2022-10-19, 20:58:04 Notice (6) DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC
Time Not Established Notice (6) Honoring MDD; IP provisioning mode = IPv6
Time Not Established Critical (3) No Ranging Response received - T3 time-out;Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-
2022-10-19, 20:56:54 Critical (3) Resetting the cable modem due to docsDevResetNow
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;
18 Replies
Please post a copy and paste of the modems connection status page.
https://kb.netgear.com/30007/How-do-I-obtain-the-cable-connection-information-from-a-NETGEAR-cable-modem-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.
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.htmlI'm going to go ahead and order new cables, should I go higher than CAT6 or will that suffice? I want to best perfomance available.
Thank you!
Your main channels have some correct and un-correcables.
I see the OFDMA channel has tons. This should be near zeros. something the ISP should help you resolve. Something to check the coax cable line and remove any splitters. Check all jack fittings and such.
Have the ISP check the signal up to the modem as well. Power on the line is a bit on the low side but in spec.CAT6 UTP is fine.
What is the distance between the modem and router?
What brand and model router are you using with the CM modem?
