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Sync timing synchronization failure
I have a Motorola Modem MB 7621. In the last few months, the cable and internet zaps out for about 2 seconds, multiple times a day. When I went into the modem event log there are dozens of sync timing synchronization failure items listed. Is this due to the age of the modem or something else?
EG
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112.2K Messages
1 month ago
Please post those error log entries in their entirety (copy and paste them, don't post a screenshot) but redact any CM MAC and the CMTS MAC addresses for your privacy. They are considered to be personal information. The posting of personally identifying information is a violation of their forum guidelines. The forum bot will not allow your post to be seen publicly.
Please also 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.
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EG
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112.2K Messages
1 month ago
This may or may not be the root cause of the problem (YMMV), but it should be addressed regardless. First.
The upstream power is good, but the downstream power is on the low / weak side and it may be intermittently fluctuating even lower to out of spec levels. That can cause random disconnects, spontaneous rebooting of the modem, speed, packet loss, latency problems, and the unbonding of channels.
In an effort to try to obtain better connectivity / more wiggle room, check to see if there are any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/reconfigured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage from Home Depot, Target, Wal-Mart, etc. Splitters should be swapped with known to be good / new ones to test.
Also, check the coax cable for any damage such as cuts, nicks, abrasions, kinks, sharp bends, animal chews.
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.
Good luck with it !
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EG
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112.2K Messages
1 month ago
Quite welcome ! Maybe yes, maybe no. The only way to tell for sure is a swap out for another. It's still on their supported devices list.
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EG
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112.2K Messages
1 month ago
@ASPENREX
Did any of the info apply ?
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