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Intermittent Connection Issues

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Intermittent Connection Issues

I am getting intermittent connection issues.  Is there any way to tell if there is a problem in the Xfinity equipment?  I am not a network engineer.  One time Customer Service confirmed a known system outage, but mostly they just report that my modem is offline.  Service usually comes back within a few minutes without my doing anything.  Spex:

Modem: CastleNet Technologies Inc. 5341J
Serial #: FC4AE90091A4
Internet Plan: Performance Pro Tier
Download Speed: 150Mbps
Upload Speed: 5Mbps

Downstream Bonded Channels
Channel    Modulation    Frequency    Power    SNR    Correctables    Uncorrectables
1    QAM256    531000000 Hz    -8.5 dBmV    39.4 dB    364    127
2    QAM256    477000000 Hz    -10.1 dBmV    39.0 dB    1020    123
3    QAM256    483000000 Hz    -9.9 dBmV    39.0 dB    858    148
4    QAM256    489000000 Hz    -9.8 dBmV    39.0 dB    487    95
5    QAM256    495000000 Hz    -9.8 dBmV    38.7 dB    574    120
6    QAM256    507000000 Hz    -9.0 dBmV    39.0 dB    678    124
7    QAM256    513000000 Hz    -8.9 dBmV    39.1 dB    495    116
8    QAM256    549000000 Hz    -9.8 dBmV    38.7 dB    554    77

Upstream Bonded Channels
Channel    US Channel Type    Symbol Rate    Frequency    Power
1    ATDMA    5120 Ksym/sec    36500000 Hz    49.5 dBmV
2    ATDMA    5120 Ksym/sec    17300000 Hz    46.8 dBmV
3    ATDMA    5120 Ksym/sec    30100000 Hz    49.5 dBmV
4    ATDMA    5120 Ksym/sec    23700000 Hz    47.8 dBmV

Startup Procedure
Procedure    Status    Comment
Acquire Downstream Channel    531000000 Hz    Locked
Connectivity State    OK    Operational
Boot State         
Configuration File    OK    
Security    Enabled    BPI+

Information
Standard Specification Compliant    DOCSIS 3.0
Hardware Version    A0
Software Version    5.5.8.6JCC
Cable Modem MAC Address    fc:4a:e9:00:91:a4
Cable Modem Serial Number    3004-5341-00-03J-1285
CM certificate    Installed


Accepted Solutions
Expert

Re: Intermittent Connection Issues

Hi @rwk2095

Your downstream power levels are marginal. They are probably fluctuating a bit and knocking you off line.  Usually, this is caused by too many splitters or bad/substandard wiring. It's possible it is a Comcast issue, but most likely the problem exists between the tap (pole) and your modem. See the troubleshooting guide.




All Replies
Expert

Re: Intermittent Connection Issues

Hi @rwk2095

Your downstream power levels are marginal. They are probably fluctuating a bit and knocking you off line.  Usually, this is caused by too many splitters or bad/substandard wiring. It's possible it is a Comcast issue, but most likely the problem exists between the tap (pole) and your modem. See the troubleshooting guide.



New Poster

Re: Intermittent Connection Issues

Thanks for the tip.  I had this problem two years ago, and it seemed to be caused by a splitter that had worked loose.  I took all the splitters out then, so it looks like I need to get a tech out here again.