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Help slow Gigabit speeds!!! Upgraded on June 16th

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Official Employee

Re: Help slow Gigabit speeds!!! Upgraded on June 16th

Hi, Nella88 - I received your private message and replied back. Thank you!

Frequent Visitor

Re: Help slow Gigabit speeds!!! Upgraded on June 16th

Readings

5448155D-B861-466D-9651-3A67B28C9277.png
Frequent Visitor

Re: Help slow Gigabit speeds!!! Upgraded on June 16th

I keep getting 8 to 10 Mbps with 35 upload. I’ve been recording short video clips of the speed test so I can actually show the next tech what is actually going on. Come on Saturday
Expert

Re: Help slow Gigabit speeds!!! Upgraded on June 16th

Awesome! Keep us update please Smiley Happy


I am not a Comcast employee, just a moderator. Pls observe Wheaton's Law.
Frequent Visitor

Re: Help slow Gigabit speeds!!! Upgraded on June 16th

Thank you! I have another tech coming here on Saturday. Hope I hear some promissing news on this issue!


@Nerdburg
Expert

Re: Help slow Gigabit speeds!!! Upgraded on June 16th

 

Hi @Nella88,

Your tech is telling you that your signal is "too hot" because it's right off the tap. He attempted to mitigate the hot signal by attenuating (reducing the amplitude) of your signal with at least one splitter. He did this because premise techs have limited tools available to them to address these issues, it's really something that should be addressed by a Line/Maintenance tech. In most of Comcast's footprint, the acceptable upstream max is actually +54dBmV, I just have more restrictive parameters listed in the troubleshooting guide since not all systems are the same. Also because of how your signal works with the return path, your upstream signal levels really aren't that high, it's just the way the modem reports it. No doubt your tech knows the local parameters and was knowledgeable enough to tell you the upstream levels are okay.

 

I've asked an employee to check the CMTS for real-time and historical RF signal reports from your modem. They can also check your local node/plant for any degradation or error reports. You can expect a reply in this thread. 

 

Ultimately you'll probably need to get another premise tech to come out and escalate the issue to the maintenance department. 

 

FYI: They owe you a $20 credit for every tech visit after the first for the same problem. You can also get a credit for your service from the time you first reported the issue until it is resolved.


I am not a Comcast employee, just a moderator. Pls observe Wheaton's Law.
Diamond Problem Solver

Re: Help slow Gigabit speeds!!! Upgraded on June 16th


@Nella88 wrote:

That is what I told the tech but he said that it was fine.

 

Hmmmmm............... It's not.

 

I told him if this doesn't solve the speed issue to just call back in.

 

Yep. If you have further problems, get them back out there until they fix it right. Good luck !

 

He also said I have very high frequency from the tap to my closet where it comes up at.

 

I have no clue what was meant by that..... He must have meant *power*, not "frequency".

 


 

Frequent Visitor

Re: Help slow Gigabit speeds!!! Upgraded on June 16th

That is what I told the tech but he said that it was fine. I told him if this doesn't solve the speed issue to just call back in. In the end, all he did was lower my power levels for my downstream and increased my upstream. He also said I have very high frequency from the tap to my closet where it comes up at.

 

 

 

Diamond Problem Solver

Re: Help slow Gigabit speeds!!! Upgraded on June 16th


@Nella88 wrote:

 

 

My upstream power levels are now 51 dbmv comapred to the 48.


FWIW, the upstream power levels are now worse.

Frequent Visitor

Re: Help slow Gigabit speeds!!! Upgraded on June 16th

The tech replaced the coax connecters on the tap, he installed a SV3G splitter (5-1002mhz) that had caps on the first 3.5dm and second 3.5 dm. The other coax cable was into the 7.5 db spot and is going into my coax wall plate then into my modem. First couple of test were around low 900's and then high 800's with 35 upload. This was all done at 9 a.m. this morning. It started going back down to 300 - 600 range after he left. I checked my CM1000 log to see if anything different has changed. 

 

My downstrean power level is now in the 2.6 dbmv   compared to the high 5 to 6 that it was before.

 

My upstream power levels are now 51 dbmv comapred to the 48.

 

Hopefully this will solve my issue around 5 p.m. - 12 a.m. otherwise I will say that it could be a bad tap or amp. I'm only guessing at this point.

 

 

Upstream Bonded Channels Channel Lock Status Modulation Channel ID Frequency Power 1 Locked ATDMA 1 35800000 Hz 51.3 dBmV 2 Locked ATDMA 2 29400000 Hz 51.3 dBmV 3 Locked ATDMA 3 23000000 Hz 51.0 dBmV 4 Locked ATDMA 4 16600000 Hz 50.5 dBmV 5 Not Locked Unknown 0 0 Hz 0.0 dBmV 6 Not Locked Unknown 0 0 Hz 0.0 dBmV 7 Not Locked Unknown 0 0 Hz 0.0 dBmV 8 Not Locked Unknown 0 0 Hz 0.0 dBmV

 

Downstream OFDM Channels Channel Lock Status Modulation / Profile ID Channel ID Frequency Power SNR / MER Active Subcarrier Number Range Unerrored Codewords Correctable Codewords Uncorrectable Codewords 1 Locked 0, 1 29 708000000 Hz 2.6 dBmV 42.5 dB 1108 ~ 2987 1185415 267751 15 2 Not Locked 0 0 0 Hz -1.5 dBmV 0.0 dB 0 ~ 4095 0 0 0

Frequent Visitor

Re: Help slow Gigabit speeds!!! Upgraded on June 16th

Thanks Comcast!!!

 

Frequent Visitor

Re: Help slow Gigabit speeds!!! Upgraded on June 16th

Could too much Down/upstream power cause the modem to have these crazy speeds? I read that the down stream should be no higher than +7 dBmV and mine in the second screen shot was at + 5.8 dBmV and even +6.3 dBmV during that screen shot at 12 a.m. Maybe the power increase is causing it to be unstable.

 

When doing speedtest, is it common for the download to climb up a peak then just naturally watch it fall middle of the downstream? It will then sometimes kick back in trying to reach were it last peak during that same speedtest. The upload will just climb to 40 -41mbps and stay stable until the end of the test.

 

Maybe that is my next hint

Diamond Problem Solver

Re: Help slow Gigabit speeds!!! Upgraded on June 16th

They are a bit on the high side and noise / an impairment in the return path can make them higher. With the way that the TCP protocol works, an impairment in the upstream / return path can affect your download speed / forward path due to TCP ACK packets not being received by / returned to the sender.

Frequent Visitor

Re: Help slow Gigabit speeds!!! Upgraded on June 16th

I'll have to check it out tonight when it starts back up at 5 p.m. I took a screen shot around 7:30 p.m with those upload channels getting 49.3 - 48.3 dB. I will have to check later tonight aroun 8 -9 p.m. It gets really really slow with packet lost of 3% and downspeeds around 8 - 2 mbps. My ping gets around 90 - 100's with my upload speeds around 10 mbps.

 

Thanks for reaching out!

Diamond Problem Solver

Re: Help slow Gigabit speeds!!! Upgraded on June 16th

Ever notice if the upstream power levels intermittently fluctuate higher in to the 51-52 dB area ?

Frequent Visitor

Re: Help slow Gigabit speeds!!! Upgraded on June 16th

I'm starting to think there might be too much noise in the line during these hour 5 p.m  - 12 a.m

 

<tabindex=-1>Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 657000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security Enable BPI+
IP Provisioning Mode Honor MDD IPv6 only

<tabindex=-1>Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR / MER Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked QAM256 33 657000000 Hz 5.3 dBmV 44.1 dB 1510281478 43 40
2 Locked QAM256 1 465000000 Hz 5.0 dBmV 45.1 dB 1508939025 31 123
3 Locked QAM256 2 471000000 Hz 5.1 dBmV 44.8 dB 1508948288 25 146
4 Locked QAM256 3 477000000 Hz 5.0 dBmV 44.7 dB 1508958556 24 128
5 Locked QAM256 4 483000000 Hz 5.0 dBmV 44.8 dB 1508966392 41 104
6 Locked QAM256 5 489000000 Hz 5.1 dBmV 44.6 dB 1508975730 29 112
7 Locked QAM256 6 495000000 Hz 4.9 dBmV 44.4 dB 1508986441 31 106
8 Locked QAM256 7 507000000 Hz 5.0 dBmV 44.9 dB 1508995218 32 95
9 Locked QAM256 8 513000000 Hz 5.5 dBmV 45.0 dB 1509007243 43 105
10 Locked QAM256 9 519000000 Hz 5.1 dBmV 44.7 dB 1509016748 24 98
11 Locked QAM256 10 525000000 Hz 5.5 dBmV 44.9 dB 1509025948 19 88
12 Locked QAM256 11 531000000 Hz 5.3 dBmV 44.8 dB 1509035156 19 73
13 Locked QAM256 12 537000000 Hz 5.4 dBmV 44.9 dB 1509044957 24 72
14 Locked QAM256 13 543000000 Hz 5.4 dBmV 44.7 dB 1509054523 18 73
15 Locked QAM256 14 549000000 Hz 5.2 dBmV 44.7 dB 1509064384 21 83
16 Locked QAM256 15 555000000 Hz 5.4 dBmV 44.7 dB 1509074040 25 86
17 Locked QAM256 16 561000000 Hz 5.1 dBmV 44.5 dB 1509083291 23 74
18 Locked QAM256 17 567000000 Hz 5.5 dBmV 44.7 dB 1509093050 15 65
19 Locked QAM256 18 573000000 Hz 5.0 dBmV 44.3 dB 1509102943 16 70
20 Locked QAM256 19 579000000 Hz 5.4 dBmV 44.5 dB 1509111984 17 73
21 Locked QAM256 20 585000000 Hz 5.2 dBmV 44.2 dB 1509121860 14 64
22 Locked QAM256 21 591000000 Hz 5.6 dBmV 44.3 dB 1509131609 20 57
23 Locked QAM256 22 597000000 Hz 5.6 dBmV 44.3 dB 1509141136 24 74
24 Locked QAM256 23 603000000 Hz 5.7 dBmV 44.6 dB 1509149190 24 64
25 Locked QAM256 24 609000000 Hz 5.8 dBmV 44.5 dB 1509159569 18 75
26 Locked QAM256 25 615000000 Hz 5.6 dBmV 44.2 dB 1509169597 28 53
27 Locked QAM256 26 621000000 Hz 5.9 dBmV 44.2 dB 1509175712 29 49
28 Locked QAM256 27 627000000 Hz 5.5 dBmV 44.3 dB 1509183767 35 39
29 Locked QAM256 28 633000000 Hz 5.8 dBmV 44.1 dB 1509188692 7 41
30 Locked QAM256 30 639000000 Hz 5.2 dBmV 44.0 dB 1509177020 37 47
31 Locked QAM256 32 651000000 Hz 5.2 dBmV 44.0 dB 1509186246 35 47
32 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0 0

<tabindex=-1>Upstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power
1 Locked ATDMA 1 35800000 Hz 48.8 dBmV
2 Locked ATDMA 2 29400000 Hz 48.3 dBmV
3 Locked ATDMA 3 23000000 Hz 48.0 dBmV
4 Locked ATDMA 4 16600000 Hz 47.5 dBmV
5 Not Locked Unknown 0 0 Hz 0.0 dBmV
6 Not Locked Unknown 0 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Hz 0.0 dBmV

<tabindex=-1>Downstream OFDM Channels
Channel Lock Status Modulation / Profile ID Channel ID Frequency Power SNR / MER Active Subcarrier Number Range Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked 0, 1 29 708000000 Hz 6.3 dBmV 42.5 dB 1108 ~ 2987 5236155 820551 0
2 Not Locked 0 0 0 Hz 1.7 dBmV 0.0 dB 0 ~ 4095 0 0 0

<tabindex=-1>Upstream OFDMA Channels
Channel Lock Status Modulation / Profile ID Channel ID Frequency Power
1 Not Locked Unknown 0 0 Hz 0 dBmV
2 Not Locked Unknown 0 0 Hz 0 dBmV

Current System Time: Wed Jun 20 00:19:44 2018 
Frequent Visitor

Help slow Gigabit speeds!!! Upgraded on June 16th

I recently moved to new apartment and I was able to use the move service to transfer my current equipment. After being in my new apartment over a month, I decided to upgrade my Comcast package to the gigabit speeds. I went to Bestbuy and bought the Arris SB8200 modem. Took it home and called Comcast to get it provisioned. Everything went fine and I had it hard wired to my computer with a usb 3.0 gigabit adapter to get the best speed test results. I was geting 620 mbps download with 41mbps upload around 1 p.m est . I started to do more speeds test that day and was getting mixed results after 5 pm est. Started to see a massive decrease in my download speeds from 5 p.m - 12 a.m. Every hour I was getting worse and worse speeds. I was doing speed test every 30 minutes. My download speed was 8 mbps with 37.1mbps at 8 p.m.

 

The next day, Sunday speeds were like in the mid 700 with 40 upload in the morning. From 8 am to 4pm the speeds would go from 800-400mbps with still the same 40 mbps upload. As soon as 5 pm hit, I started to see the same decrease in my speeds. I was looking all over the internet thinking could this just be something with my modem or maybe something with line to the main box outside my apartment complex.

 

I got home Monday around 5 P.M with my speeds at 400 mbps then slowly decreased to 5 down and 20 up around 9 p.m. I had today (Tuesday) off so I decided to run to best buy and buy another modem. I decided to keep my SB8200 just for the simple fact I wasn't sure if it was my service line in my apartment or maybe a bad modem. Bought the CM1000, activated the modem this afternoon and speed were alot better. was getting anywhere from the high 800's to high 400's during noon to 5:30 p.m. The results felt a little better with the Netgear CM1000 but it didn't solve the issue I'm having with my speeds. Still currently getting 8 mbps with now 9 mbps upload. I've been switching from computer to my Xbox One X testing speeds throughout the last couple of days. 

 

I do have a Nighthawk R7000 router that has not be used when pulling those speeds test. Everything was direct connect to the modem to my Laptop and Xbox One X.

 

Here are the logs I was able to pull from my new CM1000 modem.

 

Frequency start Value
This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.
Starting Frequency

<tabindex=-1>Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 657000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security Enable BPI+
IP Provisioning Mode Honor MDD IPv6 only

<tabindex=-1>Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR / MER Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked QAM256 33 657000000 Hz 5.0 dBmV 44.0 dB 904254798 43 40
2 Locked QAM256 1 465000000 Hz 4.6 dBmV 44.9 dB 902887825 31 123
3 Locked QAM256 2 471000000 Hz 4.8 dBmV 45.0 dB 902897209 25 146
4 Locked QAM256 3 477000000 Hz 4.7 dBmV 45.1 dB 902907051 24 128
5 Locked QAM256 4 483000000 Hz 4.6 dBmV 44.9 dB 902914972 41 104
6 Locked QAM256 5 489000000 Hz 4.7 dBmV 44.8 dB 902924746 29 112
7 Locked QAM256 6 495000000 Hz 4.6 dBmV 44.5 dB 902934823 31 106
8 Locked QAM256 7 507000000 Hz 4.7 dBmV 44.7 dB 902943839 32 95
9 Locked QAM256 8 513000000 Hz 5.1 dBmV 44.8 dB 902953392 43 105
10 Locked QAM256 9 519000000 Hz 4.8 dBmV 44.8 dB 902963365 24 98
11 Locked QAM256 10 525000000 Hz 5.2 dBmV 45.0 dB 902972218 19 88
12 Locked QAM256 11 531000000 Hz 4.9 dBmV 44.7 dB 902981459 19 73
13 Locked QAM256 12 537000000 Hz 5.1 dBmV 44.8 dB 902991108 24 72
14 Locked QAM256 13 543000000 Hz 5.0 dBmV 44.9 dB 903000248 18 73
15 Locked QAM256 14 549000000 Hz 4.8 dBmV 44.5 dB 903010531 21 83
16 Locked QAM256 15 555000000 Hz 5.1 dBmV 44.8 dB 903020044 25 86
17 Locked QAM256 16 561000000 Hz 4.8 dBmV 44.6 dB 903029186 23 74
18 Locked QAM256 17 567000000 Hz 5.1 dBmV 44.7 dB 903038795 15 65
19 Locked QAM256 18 573000000 Hz 4.6 dBmV 44.3 dB 903048039 16 70
20 Locked QAM256 19 579000000 Hz 5.0 dBmV 44.4 dB 903057146 17 73
21 Locked QAM256 20 585000000 Hz 4.8 dBmV 44.4 dB 903066649 14 64
22 Locked QAM256 21 591000000 Hz 5.2 dBmV 44.5 dB 903076237 20 57
23 Locked QAM256 22 597000000 Hz 5.2 dBmV 44.4 dB 903085284 24 74
24 Locked QAM256 23 603000000 Hz 5.4 dBmV 44.0 dB 903093936 24 64
25 Locked QAM256 24 609000000 Hz 5.4 dBmV 44.4 dB 903104253 18 75
26 Locked QAM256 25 615000000 Hz 5.3 dBmV 44.3 dB 903122467 28 53
27 Locked QAM256 26 621000000 Hz 5.5 dBmV 44.4 dB 903128046 29 49
28 Locked QAM256 27 627000000 Hz 5.1 dBmV 44.4 dB 903136057 35 39
29 Locked QAM256 28 633000000 Hz 5.4 dBmV 44.2 dB 903141553 7 41
30 Locked QAM256 30 639000000 Hz 4.8 dBmV 44.0 dB 903120250 37 47
31 Locked QAM256 32 651000000 Hz 4.8 dBmV 43.9 dB 903129595 35 47
32 Not Locked Unknown 0 0 Hz 0.0 dBmV 0.0 dB 0 0 0

<tabindex=-1>Upstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power
1 Locked ATDMA 1 35800000 Hz 49.3 dBmV
2 Locked ATDMA 2 29400000 Hz 49.0 dBmV
3 Locked ATDMA 3 23000000 Hz 48.8 dBmV
4 Locked ATDMA 4 16600000 Hz 48.3 dBmV
5 Not Locked Unknown 0 0 Hz 0.0 dBmV
6 Not Locked Unknown 0 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Hz 0.0 dBmV

<tabindex=-1>Downstream OFDM Channels
Channel Lock Status Modulation / Profile ID Channel ID Frequency Power SNR / MER Active Subcarrier Number Range Unerrored Codewords Correctable Codewords Uncorrectable Codewords
1 Locked 0, 1 29 708000000 Hz 5.9 dBmV 42.5 dB 1108 ~ 2987 3324874 564824 0
2 Not Locked 0 0 0 Hz 1.4 dBmV 0.0 dB 0 ~ 4095 0 0 0

<tabindex=-1>Upstream OFDMA Channels
Channel Lock Status Modulation / Profile ID Channel ID Frequency Power
1 Not Locked Unknown 0 0 Hz 0 dBmV
2 Not Locked Unknown 0 0 Hz 0 dBmV
 

 

Any advice would be appreciated!