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SYNC Timing Synchronization failure

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SYNC Timing Synchronization failure

Getting a lot of SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing is it my modem or signal problem ? seems to get better after modem reboot but goes down hill after a while.

 

Procedure Status Comment
Acquire Downstream Channel 541750000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Configuration File OK  
Security Enabled BPI+
DOCSIS Network Access Enabled Allowed  

 
Downstream Bonded Channels
Channel ID Lock Status Modulation Frequency Power SNR/MER Corrected Uncorrectables
13 Locked QAM256 541750000 Hz 0.0 dBmV 40.9 dB 0 0
1 Locked QAM256 463750000 Hz -0.6 dBmV 40.9 dB 0 0
2 Locked QAM256 469750000 Hz -0.5 dBmV 40.8 dB 0 0
3 Locked QAM256 475750000 Hz -0.4 dBmV 40.7 dB 0 0
4 Locked QAM256 481750000 Hz -0.5 dBmV 40.8 dB 0 0
5 Locked QAM256 487750000 Hz -0.1 dBmV 40.9 dB 0 0
6 Locked QAM256 493750000 Hz 0.1 dBmV 40.7 dB 0 0
7 Locked QAM256 505750000 Hz 0.1 dBmV 40.7 dB 0 0
8 Locked QAM256 511750000 Hz 0.1 dBmV 40.9 dB 0 0
9 Locked QAM256 517750000 Hz 0.2 dBmV 41.0 dB 0 0
10 Locked QAM256 523750000 Hz -0.1 dBmV 41.0 dB 0 0
11 Locked QAM256 529750000 Hz 0.3 dBmV 40.9 dB 0 0
12 Locked QAM256 535750000 Hz 0.4 dBmV 41.0 dB 0 0
14 Locked QAM256 547750000 Hz 0.1 dBmV 41.0 dB 0 0
15 Locked QAM256 553750000 Hz 0.1 dBmV 40.8 dB 0 0
16 Locked QAM256 559750000 Hz 0.0 dBmV 40.9 dB 0 0
17 Locked QAM256 565750000 Hz -0.1 dBmV 40.8 dB 0 0
18 Locked QAM256 571750000 Hz -0.1 dBmV 40.4 dB 0 0
19 Locked QAM256 577750000 Hz -0.2 dBmV 40.6 dB 0 0
20 Locked QAM256 583750000 Hz -0.4 dBmV 40.7 dB 0 0
21 Locked QAM256 589750000 Hz -0.1 dBmV 40.6 dB 0 0
22 Locked QAM256 595750000 Hz -0.1 dBmV 40.5 dB 0 0
23 Locked QAM256 601750000 Hz -0.2 dBmV 40.4 dB 0 0
24 Locked QAM256 607750000 Hz -0.4 dBmV 40.3 dB 0 0
25 Locked QAM256 613750000 Hz -0.2 dBmV 40.3 dB 0 0
26 Locked QAM256 619750000 Hz 0.0 dBmV 40.3 dB 0 0
27 Locked QAM256 625750000 Hz -0.1 dBmV 40.1 dB 0 0
28 Locked QAM256 631750000 Hz 0.0 dBmV 40.2 dB 0 0
29 Locked QAM256 637750000 Hz -0.2 dBmV 40.1 dB 0 0
30 Locked QAM256 643750000 Hz 0.0 dBmV 40.2 dB 0 0
31 Locked QAM256 649750000 Hz 0.0 dBmV 40.0 dB 0 0
32 Locked QAM256 655750000 Hz 0.0 dBmV 39.9 dB 0 0
159 Locked Other 690000000 Hz 0.7 dBmV 39.0 dB 78858130 0



 
Upstream Bonded Channels
Channel Channel ID Lock Status US Channel Type Frequency Width Power
1 2 Locked SC-QAM Upstream 29400000 Hz 6400000 Hz 48.0 dBmV
2 1 Locked SC-QAM Upstream 35800000 Hz 6400000 Hz 49.0 dBmV
3 3 Locked SC-QAM Upstream 23000000 Hz 6400000 Hz 49.0 dBmV
4 4 Locked SC-QAM Upstream 16600000 Hz 6400000 Hz 49.0 dBmV



 

Current System Time: Wed Jun 12 08:29:46 2019

Expert

Re: SYNC Timing Synchronization failure

The upstream power is a bit on the high side and it may be intermittently fluctuating even higher to out of spec levels. That can cause random disconnects, spontaneous re-booting of the modem, and speed and latency problems.

In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.



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