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Inconsistent speeds, occasional dropped connection

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New Poster

Inconsistent speeds, occasional dropped connection

Hello all,

 

Ive been going a little nutty trying to figure out if the issue lies with my router (Nighthawk R7000),  modem (SB6190), my house, Comcast or some combination.  I've tried a few different modems, most recently the SB6190 and the first night the speeds were great but they've been definitely fluctuating.  My plan is for 200mbps.  Right now I'm seeing around 40.  Additionally my modem seemed to lose its connection several hours ago.  

Here are the current status numbers.  I noticed two channels aren't locked (how many are supposed to be locked?) and there seems to be uncorrectables around those channels:

 

 

 
Startup Procedure
Procedure Status Comment
Acquire Downstream Channel   Locked
Connectivity State OK Operational
Boot State OK Operational
Configuration File OK  
Security Enabled BPI+
DOCSIS Network Access Enabled Allowed  

 
Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Corrected Uncorrectables
1 Locked 256QAM 16 471.00 MHz 6.00 dBmV 38.98 dB 0 0
2 Locked 256QAM 12 447.00 MHz 6.00 dBmV 38.98 dB 10 0
3 Locked 256QAM 13 453.00 MHz 6.20 dBmV 40.37 dB 10 0
4 Locked 256QAM 14 459.00 MHz 6.20 dBmV 38.98 dB 0 0
5 Locked 256QAM 15 465.00 MHz 6.10 dBmV 38.98 dB 7 0
6 Locked 256QAM 17 477.00 MHz 6.00 dBmV 38.98 dB 0 0
7 Locked 256QAM 18 483.00 MHz 6.20 dBmV 38.98 dB 18 0
8 Locked 256QAM 19 489.00 MHz 6.20 dBmV 38.98 dB 0 0
9 Locked 256QAM 20 495.00 MHz 6.20 dBmV 38.98 dB 6 0
10 Locked 256QAM 21 507.00 MHz 6.00 dBmV 38.61 dB 1 0
11 Locked 256QAM 22 513.00 MHz 6.00 dBmV 38.98 dB 0 0
12 Locked 256QAM 23 519.00 MHz 6.00 dBmV 38.98 dB 2 0
13 Locked 256QAM 24 525.00 MHz 5.90 dBmV 38.98 dB 8 0
14 Locked 256QAM 25 531.00 MHz 5.90 dBmV 38.98 dB 23 0
15 Locked 256QAM 26 543.00 MHz 5.90 dBmV 40.37 dB 9 0
16 Locked 256QAM 27 549.00 MHz 5.90 dBmV 38.98 dB 0 0
17 Locked 256QAM 28 555.00 MHz 6.30 dBmV 38.98 dB 0 0
18 Locked 256QAM 29 561.00 MHz 6.20 dBmV 38.98 dB 0 0
19 Locked 256QAM 30 567.00 MHz 6.20 dBmV 38.98 dB 0 0
20 Locked 256QAM 31 573.00 MHz 6.20 dBmV 38.98 dB 0 0
21 Locked 256QAM 32 579.00 MHz 6.40 dBmV 38.98 dB 0 0
22 Locked 256QAM 33 585.00 MHz 6.60 dBmV 38.61 dB 0 0
23 Locked 256QAM 34 591.00 MHz 6.50 dBmV 38.98 dB 0 0
24 Locked 256QAM 35 597.00 MHz 6.70 dBmV 40.37 dB 4 0
25 Locked 256QAM 36 603.00 MHz 6.70 dBmV 38.90 dB 1 0
26 Locked 256QAM 37 609.00 MHz 6.90 dBmV 39.50 dB 0 0
27 Locked 256QAM 38 615.00 MHz 6.70 dBmV 38.60 dB 242 38
28 Not Locked ---- 39 621.00 MHz ---- ---- ---- ----
29 Not Locked ---- 40 627.00 MHz ---- ---- ---- ----
30 Locked 256QAM 41 633.00 MHz 7.00 dBmV 33.30 dB 83374 18994
31 Locked 256QAM 42 639.00 MHz 6.80 dBmV 38.90 dB 3 0
32 Locked 256QAM 43 645.00 MHz 6.80 dBmV 39.50 dB 2 0

 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 2 5120 kSym/s 23.70 MHz 39.75 dBmV
2 Locked ATDMA 4 5120 kSym/s 36.70 MHz 39.25 dBmV
3 Locked ATDMA 3 5120 kSym/s 30.30 MHz 39.50 dBmV
4 Locked ATDMA 1 5120 kSym/s 17.30 MHz 39.75 dBmV

 

Another thing I noticed was that my previous modem (CM600 also had issues at the same frequencies, 615-633 MHz).  Is this something a tech would come out and fix?

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Expert

Re: Inconsistent speeds, occasional dropped connection

Yeah. Some of the downstream channels are not locking in. There is probably noise ingressing into the line somewhere at those frequencies. A tech would have the proper testing tool to locate the source.

 

In the interim, here are some things that you can try;

 

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.

 

Good luck !



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New Poster

Re: Inconsistent speeds, occasional dropped connection

Thanks, so it sounds like having all of my downstream channels locked is expected.

My cable setup is pretty easy, just a single cable line that comes into the house. No splitters or anything that I can see. I guess I’ll have a tech try to take a look. Why would it be the case that a new modem would be super fast for a few hours then regress again? Does noise “accumulate”?
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Expert

Re: Inconsistent speeds, occasional dropped connection

Noise ingress is typically variable / intermittent, though it can also be steady.



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I am a Customer Expert volunteering my time to help other customers here in the Forums.
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New Poster

Re: Inconsistent speeds, occasional dropped connection

Just following up. Another tech came out today and after I convinced him that there was probably something wrong with the line, he replace the drop line and now all of my channels are locked and I’m getting the speeds I should!
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Expert

Re: Inconsistent speeds, occasional dropped connection

Glad that it got straightened out ! Good luck ! Now closing this topic.



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I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark the post as Best Answer!