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Need help on intermittent connection issues..

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New Poster

Need help on intermittent connection issues..

Hi,

 

I recently see intermittent connection issues when browsing the Internet. Originally I thought is is a problem with my router, then find out problem still occurs when directly connect to modem. It happens randomly during the day, several times in 15 minutes. The Internet is barely usable.

 

Contacted customer service rep, but no help, the only thing they did was to restart the modem and check outages in my area, which didn't help at all. I have rebooted my modem many many times. And customer service rep has no idea about the signal level I am talking about..

 

I looked at other posts in this forum, and looks like my upstream power is too high from the spec? My modem is motorola MB8600. 

 

It has been two months now, and still happening.. Unbelivable..

 

Thanks in advance for the help..

 

Downstream status:

  1. Channel Lock Status Modulation  Channel ID  Freq. (MHz) Pwr (dBmV)  SNR (d    Corrected   Uncorrected
  2. 1      Locked          QAM256      29                 663.0           -4.3               41.0             0                0
  3. 2      Locked  QAM256  1   483.0   -3.1    42.4    0   0
  4. 3     Locked  QAM256  2   489.0   -3.8    42.0    0   0
  5. 4     Locked  QAM256  3   495.0   -3.8    41.9    0   0
  6. 5     Locked  QAM256  4   507.0   -3.5    42.0    0   0
  7. 6     Locked  QAM256  5   513.0   -3.9    41.9    0   0
  8. 7    Locked  QAM256  6   519.0   -3.3    42.0    0   0
  9. 8   Locked  QAM256  7   525.0   -4.0    41.8    0   0
  10. 9   Locked  QAM256  8   531.0   -3.8    41.7    0   0
  11. 10  Locked  QAM256  9   543.0   -4.2    41.6    0   0
  12. 11  Locked  QAM256  10  549.0   -3.7    41.9    0   0
  13. 12  Locked  QAM256  11  555.0   -3.5    41.9    0   0
  14. 13  Locked  QAM256  12  561.0   -4.2    41.5    0   0
  15. 14  Locked  QAM256  13  567.0   -3.3    41.8    0   0
  16. 15  Locked  QAM256  14  573.0   -3.1    42.0    0   0
  17. 16  Locked  QAM256  15  579.0   -4.1    41.4    0   0
  18. 17  Locked  QAM256  16  585.0   -2.9    41.8    0   0
  19. 18  Locked  QAM256  17  591.0   -2.3    41.9    0   0
  20. 19  Locked  QAM256  18  597.0   -4.1    41.2    0   0
  21. 20  Locked  QAM256  19  603.0   -2.9    41.8    0   0
  22. 21  Locked  QAM256  20  609.0   -3.1    41.5    0   0
  23. 22  Locked  QAM256  21  615.0   -3.8    41.1    0   0
  24. 23  Locked  QAM256  22  621.0   -3.1    41.4    0   0
  25. 24  Locked  QAM256  23  627.0   -3.9    41.3    0   0
  26. 25  Locked  QAM256  24  633.0   -4.1    41.3    0   0
  27. 26  Locked  QAM256  25  639.0   -3.0    41.6    0   0
  28. 27  Locked  QAM256  26  645.0   -3.9    41.1    0   0
  29. 28  Locked  QAM256  27  651.0   -4.4    41.1    0   0
  30. 29  Locked  QAM256  28  657.0   -3.7    41.3    0   0
  31. 30  Locked  QAM256  30  669.0   -3.4    41.3    0   0
  32. 31  Locked  QAM256  31  675.0   -3.6    41.1    0   0
  33. 32  Locked  OFDM PLC    159 745.0   -3.5    39.8    0   0

Upstream status:

  1.    Channel  Lock Status Channel Type    Channel ID  Symb. Rate (Ksym/sec)   Freq. (MHz) Pwr (dBmV)
  2. 1   Locked  SC-QAM  4   5120    23.7    56.8
  3. 2   Locked  SC-QAM  1   5120    30.1    58.3
  4. 3   Locked  SC-QAM  2   5120    36.5    58.8
  5. 4   Locked  SC-QAM  3   5120    17.3    56.3

 

 

Expert

Re: Need help on intermittent connection issues..

 You are correct, your upstream levels are too high. This is typically due to configuration issues or bad connectors/splitters/coax. Remove any unneeded splitters or try another outlet. 

 

Tip: If you need service, sign up for the Service Protection Plan (SPP). It's around $6 a month and you must keep it for at least 60 days after your service call. If you have SPP, you won't incur a service charge. You can sign up when you schedule an appointment.

 

See the troubleshooting guide.


I am not an employee.
Admin1

Re: Need help on intermittent connection issues..

Hi doracat2013 -- The link provided by nerdburg is an excellent way to resolve any connectivity issue. We can assist you if you've tried those steps and continue to see connectivity issues. Please let us know if you need additional assistance. 

New Poster

Re: Need help on intermittent connection issues..

I happen to follow the guidance provided by nerdburg, and found a faulty splitter in the middle, which drops my upstream pwr to 46-48 which is still bit high, but looks like it come back to normal now.

 

Thanks.

New Poster

Re: Need help on intermittent connection issues..

One additional question @ComcastZach and others:

 

I try to set my DNS to 1.1.1.1 several days ago, and happens to be some connection issues randomly due to DNS. Just curious if comcast has any equipment in the middle that mis-use 1.1.1.1, so the DNS request fails randomly.

 

Thanks.

Silver Problem Solver

Re: Need help on intermittent connection issues..


@doracat2013 wrote:

One additional question @ComcastZach and others:

 

I try to set my DNS to 1.1.1.1 several days ago, and happens to be some connection issues randomly due to DNS. Just curious if comcast has any equipment in the middle that mis-use 1.1.1.1, so the DNS request fails randomly.

 

Thanks.


I tested 1.1.1.1 and it didn't prove to be any better than Comcast DNS.

 

Read the directions closely:

https://www.grc.com/dns/benchmark.htm

I am not a Comcast Employee.
I am just a customer, volunteering my time to help other customers here in the Forums.
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Admin1

Re: Need help on intermittent connection issues..

doracat2013 -- Traditionally 1.1.1.1 has been used as a testing IP on many local networks and WANs. As a result, when Cloudflare struck a deal to use this IP for their primary DNS resolver, it initially caused some problems with traffic routing. It's at a point where though you shouldn't see any intermittent issues though. It should either succeed or it should fail. 

 

What you can try is use your secondary resolver 1.0.0.1 to see if the issue can be replicated. If it can't be replicated on that IP then please send me PM with your account information so we can take a closer look at this. While we do not support third-party DNS providers, we do have a responsibility to ensure that the traffic is handled appropriately across our network.