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Slow/dropped connections; 4 Downstream channels 0db SNR

New Poster

Slow/dropped connections; 4 Downstream channels 0db SNR

I've been experiencing this problem since I moved into my house 6 months ago. I'm subscribed to 200+mbs but it's been stuck at 30mbs down and ~5-10mbps up. Recently, it's dropped even further and cuts out briefly sometimes. I've reset both the modem and gateway numerous times to no avail. The cable from the outside goes directly into the modem with no splitters. I'm almost positive that this is a problem between the pole and the house, but there is no line of customer support that will let me schedule a technician, due to COVID. Is there anything else that can be done to fix this? Thanks


Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Corrected Uncorrectables
1 Locked QAM256 9 555000000 Hz 3.3 dBmV 43.9 dB 0 0
2 Locked unknown 1 507000000 Hz -33.2 dBmV 0.0 dB 3572 18447
3 Locked unknown 2 513000000 Hz -33.5 dBmV 0.0 dB 0 0
4 Locked unknown 3 519000000 Hz -31.3 dBmV 0.0 dB 0 0
5 Locked unknown 4 525000000 Hz -24.0 dBmV 0.0 dB 0 0
6 Locked QAM256 5 531000000 Hz -20.2 dBmV 0.0 dB 0 0
7 Locked QAM256 6 537000000 Hz -10.2 dBmV 33.9 dB 8 0
8 Locked QAM256 7 543000000 Hz -2.1 dBmV 40.1 dB 0 0
9 Locked QAM256 8 549000000 Hz 1.9 dBmV 43.5 dB 0 0
10 Locked QAM256 10 561000000 Hz 3.7 dBmV 43.9 dB 0 0
11 Locked QAM256 11 567000000 Hz 4.0 dBmV 43.7 dB 0 0
12 Locked QAM256 12 573000000 Hz 4.0 dBmV 43.7 dB 0 0
13 Locked QAM256 13 579000000 Hz 4.1 dBmV 43.6 dB 0 0
14 Locked QAM256 14 585000000 Hz 4.0 dBmV 43.5 dB 0 0
15 Locked QAM256 15 591000000 Hz 4.1 dBmV 43.4 dB 0 0
16 Locked QAM256 16 597000000 Hz 3.8 dBmV 43.3 dB 0 0


Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 2 5120 Ksym/sec 29400000 Hz 46.8 dBmV
2 Locked ATDMA 1 5120 Ksym/sec 35800000 Hz 46.8 dBmV
3 Locked ATDMA 3 5120 Ksym/sec 23000000 Hz 46.8 dBmV
4 Locked ATDMA 4 5120 Ksym/sec 16600000 Hz 45.3 dBmV



Re: Slow/dropped connections; 4 Downstream channels 0db SNR

In a self troubleshooting effort to try to obtain better connectivity, check to see if there are there 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 types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

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.

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New Poster

Re: Slow/dropped connections; 4 Downstream channels 0db SNR

Thanks for your response. There are no splitters, aside from one possibly in the comcast box on the side of the house. The closest I can get to that is in the attic where there are two coax lines ran in from the outside. One of them is connected to the cable running to the modem by a coupler. The other one is disconnected from anything. I've tried hooking up to the second line, and don't get any connection at all. I've also tried connecting the original line to other coax lines throughout the house and moving the modem around. I experience the same quality of connection, so I'm pretty confident all of the house wiring is good. This leaves the coupler (unlikely, but I will test), the line from the outside box into the attic, and everything between the pole to the house. 

I should also mention that the previous owners had Directv for many years, and I did a self-installation when we moved in. This issue has existed for as long as I've lived at the house, which is now over 6 months. My suspicion is that it's an issue outside. Since it was a self-installation, the quality was never verified by a technician. The box/wires could very well have been damaged over the years with no one knowing since they were on satellite.


Again, there's no line of support for me to schedule a technician visit, because of COVID. This is unfortunate, because I feel like the problem can be solved by repairs 100% outside the house.