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Connection dropping/spiking

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New Poster

Connection dropping/spiking

I've been having connection issues since latest service restoration, Connection keeps dropping from time to time impacting performance. It's a very similar issue as before which was resolved by a tech. He said it was the problem was at the pole. He had to replace the cable with a new one. This fixed the problem for awhile... until hurricane Irma came and now everything is progressing slowly towards the past. Last time we were charged 60 dollars for the fix even when Comcast themselves said: " you will not be charged if the problem is not your fault ".  Last time I even bought a new modem replaced cables... I just couldn't take the spikes. All to have a Comcast tech come and rip off. When the problem was at light pole all along. well anyways here the Event log. I believe its the light pole again or one nearby but I can't-do anything about it since it's illegal so I hope I can get my service in good condition once again. Thank you. 

And yes cables are well connected and tighten. 

 

 

Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:4... 
 Time Not Established   Notice (6)   Honoring MDD; IP provisioning mode = IPv6 
 Sat Sep 16 13:15:01 2017    Warning (5)   Dynamic Range Window violation 
 Tue Sep 19 07:47:22 2017    Critical (3)   SYNC Timing Synchronization failure - Failed to receive MAC ... 
 Tue Sep 19 07:47:28 2017    Warning (5)   MDD message timeout;CM-MAC=00:40:36:42:61:12;CMTS-MAC=00:ca:... 
Diamond Problem Solver

Re: Connection dropping/spiking

Start with the modem's signal stats. Perhaps they already are, or they are close to being out of spec and intermittently they go completely of spec. Try getting them here http://192.168.100.1 or here http://10.0.0.1

Please post the *Downstream Power Level*, the *Upstream Power Level*, and the *SNR* (Signal to Noise Ratio) numbers.

What is the exact make and model number of the modem ?

Is this a WiFi connection ?
New Poster

Re: Connection dropping/spiking

http://prntscr.com/gokdkc  Here is a screenshot of Upstream and Downstream channels and latest event log. 

 

Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire FEC ... 
 Time Not Established   Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/... 
 Time Not Established   Critical (3)   No Ranging Response received - T3 time-out;CM-MAC=00:40:36:4... 
 Time Not Established   Notice (6)   Honoring MDD; IP provisioning mode = IPv6 
 Sat Sep 16 13:15:01 2017    Warning (5)   Dynamic Range Window violation 
 Tue Sep 19 07:47:22 2017    Critical (3)   SYNC Timing Synchronization failure - Failed to receive MAC ... 
 Tue Sep 19 07:47:28 2017    Warning (5)   MDD message timeout;CM-MAC=00:40:36:42:61:12;CMTS-MAC=00:ca:... 
 Fri Sep 22 14:05:23 2017    Critical (3)   SYNC Timing Synchronization failure - Failed to acquire QAM/...
New Poster

Re: Connection dropping/spiking

Model: MB7220,  and yes Indeed it's wireless connection if you wish for me to connect it directly then I will. 

Diamond Problem Solver

Re: Connection dropping/spiking

What you posted are the error log entries, not what was requested, the signal stat figures. And yes, we want to compare if this is a WiFi only problem or if affects both..
New Poster

Re: Connection dropping/spiking

"http://prntscr.com/gokdkc  Here is a screenshot of Upstream and Downstream channels and latest event log. ", It's not that hard to read. If you do not trust the link then maybe you need an antivirus or an URL checker. If you don't trust other people's URL what makes you think I should trust yours? BTW just click the link and you will have what you requested. Thank you. 

Diamond Problem Solver

Re: Connection dropping/spiking

For realz ??

 

I have an A/V of course. This isn't my first rodeo....

 

I overlooked the link, sorry.

 

And yes. Take the router out of the mix temporarily for a test.

 

The stats as read at the modem level at that moment in time were o/k but there are three additional signal stats that can cause thise errors which can't be read by the modem. They can only be read from their end by them polling the CMTS (Cable Modem Termination System) at the local headend facility.

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.

You can call in and ask what these figures are. The Upstream Receive Power Level should fall within the range of -2dB to +2dB with 0dB being in the middle and perfect.

The Upstream SNR should be least 31dB, and the higher it is the better.

The ICFR should be no higher than 2 dB.

You could have an intermittent noise ingress issue in only the upstream channel(s) / return path only somewhere.

They will be able to see whether or not everything is in the green zone and also see a history plot for the modem.