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SYNC Timing Synchronization failure / Started Unicast Maintenance Ranging - No Response received

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SYNC Timing Synchronization failure / Started Unicast Maintenance Ranging - No Response received

Hello all,

 

I'm having dropping issues with my Netgear C7800.  I've researched and done just about everything.  From factory reset to checking my connections.  I have to unplug and reset my router at least a couple of times a day.  I've seen other posts with this same issue, but no clear resolution.  Can someone help me?  Here is the event log:

 

Time Priority Description
2019-03-12, 20:35:10 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Notice (6) Honoring MDD; IP provisioning mode = IPv6
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-03-06, 22:04:10 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-03-06, 02:17:46 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-03-03, 22:11:22 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-03-03, 21:35:22 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-02-28, 19:46:10 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-02-26, 22:08:49 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-02-26, 20:18:50 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-02-25, 04:23:05 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-02-24, 21:58:32 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-02-23, 22:03:20 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-02-22, 09:54:23 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-02-21, 00:01:29 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2019-02-20, 21:57:43 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) No Ranging Response received - T3 time-out;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:01:5c:86:62:4a;CM-QOS=1.1;CM-VER=3.1;
Time Not Established Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:4c:2b:70;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

 

I ran the Diagnostics and got this:

 

PING 192.168.0.1 (192.168.0.1): 64 data bytes

72 bytes from 192.168.0.1: seq=0 ttl=64 time=0.207 ms

72 bytes from 192.168.0.1: seq=1 ttl=64 time=0.153 ms

72 bytes from 192.168.0.1: seq=2 ttl=64 time=0.157 ms

 

--- 192.168.0.1 ping statistics ---

3 packets transmitted, 3 packets received, 0% packet loss

round-trip min/avg/max = 0.153/0.172/0.207 ms

 

System Statistics:

 

System Up Time 05:54:42
Port Status TxPkts RxPkts Collisions Tx B/s Rx B/s Up Time
WAN Link Up 2762593 1039050 0 1322 6852 05:53:31
LAN1 1000M/Full 336071 482015 0 417 393 05:54:29
LAN2 100M/Full 05:54:28
LAN3 Link Down --
LAN4 100M/Full 05:54:28
2.4G WLAN b/g/n 1000M 4374917 1783427 121845766 2021 734 05:54:02
5G WLAN a/n/ac 2165M 1130921 569424 0 65797 5147 05:54:18

 

Cable Connection:

 

<tabindex=-1>Startup Procedure</tabindex=-1>
Procedure Status Comment
Acquire Downstream Channel 477000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security ENABLED BPI+
IP Provisioning Mode Honor MDD IPv6 only

<tabindex=-1>Downstream Bonded Channels</tabindex=-1>
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectabables
1 Locked QAM256 2 477000000 Hz 4.8 dBmV 43.3 dB 0 0
2 Locked QAM256 1 471000000 Hz 4.8 dBmV 43.2 dB 0 0
3 Locked QAM256 3 483000000 Hz 4.9 dBmV 43.3 dB 0 0
4 Locked QAM256 4 489000000 Hz 4.7 dBmV 43.2 dB 0 0
5 Locked QAM256 5 495000000 Hz 4.9 dBmV 43.2 dB 0 0
6 Locked QAM256 6 507000000 Hz 4.8 dBmV 43.3 dB 0 0
7 Locked QAM256 7 513000000 Hz 4.9 dBmV 43.4 dB 0 0
8 Locked QAM256 8 519000000 Hz 4.9 dBmV 43.4 dB 0 0
9 Locked QAM256 9 525000000 Hz 4.8 dBmV 43.4 dB 0 0
10 Locked QAM256 10 531000000 Hz 4.8 dBmV 43.4 dB 0 0
11 Locked QAM256 11 537000000 Hz 4.8 dBmV 43.3 dB 0 0
12 Locked QAM256 12 543000000 Hz 4.7 dBmV 43.3 dB 0 0
13 Locked QAM256 13 549000000 Hz 4.7 dBmV 43.3 dB 0 0
14 Locked QAM256 14 555000000 Hz 4.7 dBmV 43.2 dB 0 0
15 Locked QAM256 15 561000000 Hz 4.7 dBmV 43.2 dB 0 0
16 Locked QAM256 16 567000000 Hz 4.6 dBmV 42.9 dB 0 0
17 Locked QAM256 17 573000000 Hz 4.6 dBmV 43.1 dB 0 0
18 Locked QAM256 18 579000000 Hz 4.5 dBmV 42.8 dB 0 0
19 Locked QAM256 19 585000000 Hz 4.6 dBmV 42.9 dB 0 0
20 Locked QAM256 20 591000000 Hz 4.5 dBmV 42.8 dB 0 0
21 Locked QAM256 21 597000000 Hz 4.6 dBmV 42.8 dB 0 0
22 Locked QAM256 22 603000000 Hz 4.6 dBmV 42.8 dB 0 0
23 Locked QAM256 23 609000000 Hz 4.3 dBmV 42.7 dB 0 0
24 Locked QAM256 24 615000000 Hz 4.2 dBmV 42.6 dB 0 0
25 Locked QAM256 25 621000000 Hz 4.3 dBmV 42.6 dB 0 0
26 Locked QAM256 27 633000000 Hz 4.3 dBmV 42.5 dB 0 0
27 Locked QAM256 28 639000000 Hz 4.2 dBmV 42.4 dB 0 0
28 Locked QAM256 29 645000000 Hz 4.3 dBmV 42.4 dB 0 0
29 Locked QAM256 30 651000000 Hz 4.1 dBmV 42.2 dB 0 0
30 Locked QAM256 31 657000000 Hz 4.1 dBmV 42.2 dB 0 0
31 Locked QAM256 32 663000000 Hz 4.1 dBmV 42.1 dB 0 0
32 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0

<tabindex=-1>Upstream Bonded Channels</tabindex=-1>
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 18 5120 Ksym/sec 23700000 Hz 37.0 dBmV
2 Locked ATDMA 17 5120 Ksym/sec 17300000 Hz 37.0 dBmV
3 Locked ATDMA 19 5120 Ksym/sec 30300000 Hz 37.0 dBmV
4 Locked ATDMA 20 5120 Ksym/sec 36700000 Hz 37.0 dBmV
5 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0 dBmV
6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0 dBmV
7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0 dBmV
8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0 dBmV

<tabindex=-1>Downstream OFDM Channels</tabindex=-1>
Channel Channel ID Indicator Subcarrier Zero Frequency Active Subcarrier Number Range Total Codewords Uncorrectable Codewords
1 48 Non-Primary 722600000 Hz 1408 ~ 2687 86384269 0
2 0 Other 0 Hz 0 ~ 0 0 0

<tabindex=-1>Upstream OFDMA Channels</tabindex=-1>
Channel UpstreamIsMuted Ranging Status Subcarrier Zero Frequency Active Subcarrier Number Range Symbols Per Frame Tx Power
1   Other 0 Hz 0 ~ 0 0 0 dBmV
2   Other 0 Hz 0 ~ 0 0 0 dBmV
 
Highlighted
Expert

Re: SYNC Timing Synchronization failure / Started Unicast Maintenance Ranging - No Response received

The power levels and the SNR's look o/k. The error log entries, not so much... 

 

Is this with a WiFi connection ? If so, for a test, does a computer hardwired directly to the 7800 with an ethernet cable have the same problem ?

 

What are the Upstream, the Downstream, and the Internet indicator lights doing when you are experiencing these "drops" ?



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New Poster

Re: SYNC Timing Synchronization failure / Started Unicast Maintenance Ranging - No Response received

Thank you EG for your reply.  I belive it does happen with the wired eithernet connection as well.  I have trouble with my PS4 accessing Netflix when the phones and computers (connected via wifi) drop.

 

The indicator lights on the router look normal (the're only three).

 

I have tested the down and up streams via speedtest.net.  When I do, the site can not find a server and aborts.  This is when I know I have to reboot everything.

Expert

Re: SYNC Timing Synchronization failure / Started Unicast Maintenance Ranging - No Response received


@amesdude25 wrote:

 

 I belive it does happen with the wired eithernet connection as well.  

Are you sure that it happens with a hardwired connection as well ?



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New Poster

Re: SYNC Timing Synchronization failure / Started Unicast Maintenance Ranging - No Response received

Well, I guess I'm not 100% sure, no.  Is there a test I can do?

Expert

Re: SYNC Timing Synchronization failure / Started Unicast Maintenance Ranging - No Response received

Just see if it happens with a hardwired connection too. We are trying to determine if it is an overall connectivity with the Comcast system issue or a WiFi only issue.



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