Internet connectivity issues

All of the downstream channels SNR values are too low / out of spec. It appears that there is spurious noise ingress leaking into the line(s) somwhere. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the un-bonding of channels.

Here are some things that you can try to see if they apply but you may need a tech out to investigate and correct this one;

In an effort to try to obtain better connectivity, check to see if there are 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 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, etc.

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 !

You're welcome ! Everything is already in black and white.... Good luck !

@user_v93vc5 @XfinityBenjaminM 

Please circle back here and post any possible solutions for the issue here in these open public forums so that all readers here may benefit from the exchange / info. This is in keeping with the spirit for which these public help forums were originally intended. Thank you.

A Comcast technician came out to the house this weekend and confirmed our signal was strong at the street side but was weak at the modem. After doing some investigative work, he determined the source of the issue where our home was connected to the street (source). Adjustments were made and all is well.

There was also a monster splitter that was likely put into place when we had triple play, which we no longer have, and this also strengthened our internet connection. 

Case closed. 

Thanks for the update ! For curiosity, would you please post what the signal values look like now ? Thanks.

Here is an updated Connection log: 

So the SNR's are a bit better but they are still on the low side. We'd like to see them even higher. Mine are at 43-44 dB. And there are a fair number of uncorrectable bit errors. Seems more work needs to be done. Good luck with it ! 

It can't be fixed remotely. It requires boots on the ground.  And bear in mind that if the premises facing techs can not find or fix a problem at your home, it is they who are responsible for escalating it up to their line / network / maintenance dept. techs. The problem may lie beyond your home in the local neighborhood infrastructure somewhere but it is their S.O.P. to start at the home. And if the problem is found to be on their side of the demarcation point, there will not be any charge.