3 Messages
Help please - SYNC Timing Synchronization failure - after 2024 spring speed upgrade
the wifi speed has been getting worse. my plan “superfast” 800Mbps was upgraded by Xfinity last spring from 600 Mbps and lately i get barely 100Mbps and even less when one foot away from wifi. i was on a support chat with a tech today. they reset the modem, reinstalled the firmware on my Netgear C7000v2 at least 3-4 times. the speed is even slower now 34Mbps. It's actually 20% faster with my VPN turned on now.
I have 2 types of logs. one with non-helpful to this situation like DHCP IP and all the DoS Attacks but the timestamp also changed to 1970 when the firmware was installed; but the time is still off by about 2-3 mins . how can the speed be even slower from 110 to 34 after xfinity reset the router?
not to be overly skeptical but I felt like I was being sold on new equipment that I do not want any. Xfinity owned Wi-Fi router in my house even if it's lightning speed my privacy is much more important to me so getting their latest router is not an option. I do not mind buying a brand new wi-Fi 6E or seven but I don't think there is anything wrong with this router, other than the times synch being off resulting in maintenance not being able to complete. Everything seemed to be working relatively fine until shortly after the new upgrade maybe it's unrelated, but I am seeing other customers reporting the same kind of problem after the upgrade. Which was a very nice gesture to help their customers. I wonder if there was any ulterior motive like maybe people couldn't reach the speed they're paying for and they would have to get a new router. i really can not afford a new router i’m having a hard time already with the $250 cable bill with $109 internet that is at a turtles pace and trouble streaming netflix.
Can someone help me with getting the correct time Sync? or any other ideas on what i could do to increase speed on the router i have.
|
[Time synchronized with ToD server] |
1 |
Sun Feb 16 18:07:45 2025 |
|
[Initialized, firmware version: V1.03.08] |
1 |
Thu Jan 01 00:00:38 1970 |
|
[Internet disconnected] |
1 |
Sun Feb 16 18:06:05 2025 |
|
[Internet connected] IP address: [Edited: "Personal Information"] |
1 |
Sun Feb 16 17:04:13 2025 |
|
[Time synchronized with ToD server] |
1 |
Sun Feb 16 17:04:10 2025 |
The error logs show a time sync issue as far back as October of last year probably more but the dates say 1970. but anytime Xfinity tried to "Started Unicast Maintenance Ranging - No Response received -“ the correct day and time is in the log. the router clock is off by about 2 mins.
The error logs time
|
Time |
Priority |
Description |
|
1970-1-1, 00:00:48 |
Notice (6) |
Honoring MDD; IP provisioning mode = IPv6 |
|
1970-1-1, 00:00:40 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
1970-1-1, 00:00:39 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
2025-2-16, 17:02:30 |
Critical (3) |
Resetting the cable modem due to docsDevResetNow |
|
1970-1-1, 00:00:38 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
2025-2-16, 15:47:52 |
Critical (3) |
Resetting the cable modem due to docsDevResetNow |
|
2025-2-8, 19:06:26 |
Critical (3) |
Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.0; |
|
2025-2-3, 09:21:00 |
Critical (3) |
Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.0; |
|
2025-1-15, 00:46:14 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
2025-1-15, 00:46:13 |
Critical (3) |
SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.0;CM-VER=3.0; |
|
2025-1-15, 00:45:11 |
Critical (3) |
No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.0;CM-VER=3.0; |
|
2025-1-15, 00:44:18 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
2025-1-15, 00:44:18 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
2025-1-15, 00:43:26 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
2025-1-15, 00:43:25 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
2025-1-15, 00:43:18 |
Critical (3) |
Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.0; |
|
2025-1-15, 00:43:18 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.0; |
|
2025-1-15, 00:43:17 |
Critical (3) |
Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.0; |
|
2025-1-15, 00:42:35 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.0; |
|
2025-1-15, 00:42:28 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.0; |
|
2025-1-15, 00:42:24 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.0; |
|
2025-1-3, 11:40:49 |
Critical (3) |
Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.0; |
|
1970-1-1, 00:00:38 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
2024-10-24, 00:15:22 |
Critical (3) |
Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.0; |
|
1970-1-1, 03:48:16 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
1970-1-1, 03:48:15 |
Critical (3) |
No UCDs Received - Timeout;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
1970-1-1, 03:47:58 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
1970-1-1, 03:47:57 |
Critical (3) |
No UCDs Received - Timeout;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
1970-1-1, 03:47:40 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
1970-1-1, 03:47:39 |
Critical (3) |
No UCDs Received - Timeout;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
1970-1-1, 03:47:22 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
1970-1-1, 03:47:21 |
Critical (3) |
No UCDs Received - Timeout;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
1970-1-1, 03:47:04 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
1970-1-1, 03:45:51 |
Critical (3) |
No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.0;CM-VER=3.0; |
|
1970-1-1, 03:45:07 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
1970-1-1, 03:45:06 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
1970-1-1, 03:45:05 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
|
1970-1-1, 03:45:01 |
Critical (3) |
SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=xx:xx:xx:xx:xx:xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0; |
EG
Expert
•
110K Messages
2 months ago
FWIW. The time value doesn't matter. It's just a passive timestamp for general references. It can't affect the performance. The device doesn't have a built-in clock. It gets the time info on the fly from the ISP's ToD ( Time of Day) server. If there is no connection to the internet, it can't get that info, and the time/ date stamp will default to that 1970 value. The "SYNC Timing Synchronization failure" messages are caused by a communication problem between the modem and the Comcast system. Typically it is a signal problem / noise ingress into the line(s) somewhere. That being said, something else is going on. For curiosity, what do the modem's signal status values look like ? Get them in the same general area that you got the error log entries.
Please copy all of the text in its entirety of the *Downstream Power Levels*, the *SNR's* (Signal to Noise Ratios), and the *Upstream Power Level* numbers and paste them into your next post.
(edited)
2
0
EG
Expert
•
110K Messages
2 months ago
@William131
The "SNR's" are there (seventh column from the left) and they are in spec. The signal status values at that snapshot in time were OK, but the error log entries indicate that something is going on. Perhaps there is noise ingress into the line(s) / an upstream channel / return path impairment somewhere.
There are other signal stat values that can't be read by the modem. They are the "Upstream Rx Power" (Upstream Receive Power Level), the "Upstream SNR Ch." (Upstream Signal To Noise Ratio), and the "Upstream ICFR" (In Channel Frequency Response). These are as equally important in diagnosing connectivity issues as are the modem's stats.
I'm going to escalate your issue to the Comcast corporate employees (The Digital Care Team) who are available to these boards. They will be able to poll the CMTS (Cable Modem Termination System) to check for any real-time degradation and / or error reports, see your node / cable plant, and modem health, and see whether or not everything is in the green zone. They can also see a history plot for the modem and those upstream receive signal stats.
You should get a reply here in your topic. Good luck !
0
0