Issues with ISP Downstream and Upstream Speeds and Signal levels.

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Deloss92
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Issues with ISP Downstream and Upstream Speeds and Signal levels.

Post by Deloss92 »

Hi guys first post here. So I have Zito Media. I previously had 100Mbps/10Mbps. Recently upgraded my Plan to 1000Mbps/50Mbps. I have had nothing but issues since I did. The tech who installed it brought the new modem in unplugged the old one and plugged the new one in. I asked if that was it he said yep. Should take about 15Min and it will be up and running. Didn't even wait around to test it. This was around my lunch hour (Friday) so i left back to work. When i got home the internet was not working. I restarted the modem. still nothing. upstream downstream lights were blinking blue. Called Zito they said my modem was still downloading the firmware and was taking longer than usual to complete. they checked into it a little more and found that my signal levels were really low. They said give it overnight and see what its doing tomorrow. Next morning (Saturday) Great the Internet is working speeds no where near 1000Mbps and not even the 60% they guarantee. But hey im getting 400Mbps down so i wasn't complaining to much. (Sunday afternoon) Internet goes out i restart the modem wait for it to sync back up no internet. I call and they tell me my signal levels are really low and this is due to a amplifier in my area that is also creating issues for 5 other nodes according to them. They put out a maintenance request and get it completed Monday afternoon. Monday after work the internet is not working but signal levels are fine but not the best. I call and they start running some tests... They say my modem is perfectly fine and I should have internet. They start going through the normal troubleshooting steps with me... Check cables, plug directly into modem no router in-line. I can ping google.com and get consistent ping time. No internet traffic. "very Odd" Spend about 1hr30min on the phone with this tech support they are starting to get fed up and start questioning me and my equipment. I explained I have 6 different devices that were all able to browse the internet over the weekend and all of a sudden they can't and its my equipment no no no.... So I finally say ok run a speed test from your side and tell me what speeds im getting. She huffs and puts me on hold. Shes being very rude at this point. She gets back on and explains ok yeah we do see an issue with the modem im putting a tier 2 request in give it 24/48 hrs and call back. so i have no internet for 4 days. I finally get ahold out of desperation a 6db attenuator and put it inline. Shockingly I have internet now signal levels vary from -4.00dBvm to -6.700dBvm between all 32 channels. I leave it alone because the internet is working around 480Mbps/10Mbps all fine and dandy as long as i have internet. call back about 6 days later they said there was a signal level issues but it has been resolved via maintenance request. I said great. so i unplug the 6db attenuator plug modem back in and its exactly the same as before. No upload download whatsoever and signal levels are range from 0.700dBmv all the way to 1.800dBmv. I explain to them I have a 6db attenuator that I can put back on and test they say its here nor there and it probably wont fix anything. Surprisingly enough i get it plugged back in the modem syncs up and I magically have internet again. Word for word the lady goes. Thank you for calling Zito Media Have a great day and hangs up on me. I call back and get another person who was obviously filled in. He says well we have a ticket to tier 2 technicians and they will look into it.

TLDR.....
Serious Internet issues with Zito media After upgrading to Gigabit internet. Possible Signal level issues/Giving me the run around due to problems and trying to buy time.. Can't get them to admit its a signal level issues. explained by putting a 6db attenuator in line and it working just fine. without 6db attenuator it drops off and is terrible without it.
Any suggestions

Issues:
(1): Questionable Signal levels
(2): Internet is off and on throughout the day
(3): Questionable Technicians ability to fix issues.
(4): I believe there internet is having serious issues and they are coming up with these "Problems" to by time
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Philip
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Post by Philip »

Welcome to SG and thank you for sharing!

Unfortunately, first tier technical support usually has no idea what signal levels mean, and what they should be, they just read solutions from a script and take you through the motions of unplugging your modem, connecting your client device directly to their modem bypassing any routers, etc. etc. To actually get signal level readings, etc. you may have to have a tech at your premises.

Great catch on reading your own signal levels and adding an attenuator, just keep in mind that it may also increase your upstream power too much and you don't really want that. Have you tried with simply a 2-way splitter (3.5db attenuation)? I don't know what your signal levels are, but you may also want to check with this reference: https://www.speedguide.net/faq/what-cab ... ed-good-78
Raffy
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Location: Toronto, Canada

Post by Raffy »

Hello. I am new and not sure how this forum works but I need some input. My internet was only bonding to 1 or sometimes 2 upstream channels. I changed all the cables and connectors and I have no splitters. Now all seems good but and I am bonding to all 4 channels that my Thompson 476 cable modem supports. The issue is, channel 8 on downstream has a BER >5%. What could be causing it? If there was something wrong with the new cable or connectors wouldn't all the channels be out of spec? ISP came and of course they said everything was fine.

Status Code: Operational
Software Version: STAC.02.50
Software Model: a81a
Bootloader: 2.3.1

Cable Signal Details
Forward Path:
Channel Frequency Power SNR BER Modulation
1 591.0 MHz 1.3 dBmV 41.4 dB 0.000 % 256 QAM
2 585.0 MHz 1.4 dBmV 41.3 dB 0.000 % 256 QAM
3 579.0 MHz 1.8 dBmV 41.9 dB 0.000 % 256 QAM
4 597.0 MHz 0.6 dBmV 41.2 dB 0.000 % 256 QAM
5 603.0 MHz -0.3 dBmV 40.8 dB 0.000 % 256 QAM
6 609.0 MHz -1.2 dBmV 40.6 dB 0.000 % 256 QAM
7 615.0 MHz -1.1 dBmV 40.8 dB 0.000 % 256 QAM
8 621.0 MHz -2.1 dBmV 36.2 dB 5.719 % 256 QAM
Return Path:
Channel ID Frequency Power Modulation
4 38.7 MHz 49.3 dBmV 64 QAM
2 25.9 MHz 47.3 dBmV 64 QAM
3 32.3 MHz 49.3 dBmV 64 QAM
1 21.1 MHz 46.8 dBmV 64 QAM
Data Service Details
Provisioned Address: Yes
Provisioned Time: Yes
Provisioned Configuration: Yes
Registered: Yes
BPI: Enabled
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Philip
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Post by Philip »

Seems that your upstream power is still a bit high (modem has to "yell" loudly to be heard upstream), but within specs.

The BER only on certain frequency would have to be examined by a technician upstream of your modem though, to figure out where the problem is exactly, it could be at the node, or cabling/connectors anywhere in between. It is possible to have higher error rate (BER/packet loss) at certain frequency.
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Deloss92
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Post by Deloss92 »

Hey Philip,
I first want to say thank you for welcoming me to SG and to also Profusely Apologize for this long long delayed reply.

Secondly I wanted to come back and explain the issues that I found and fixes that were done to resolve my issue. Mainly to help anyone who may be on Docsis 3.1.

As it may already be known "on this forum" a lot of Docsis 3.1 modems With an Intel Chipset suffer from a Manufacturer defect with the Intel Puma Chipset. This defect Causes drop offs of the upload/download channels and severe Latency spikes. Also Vulnerability defect.

The Channels drop offs and signal level issues I was having can all be traced back to the Modem that was provided to me "Hitron Coda 4589" This modem does have the Intel Puma Chipset. After doing alot of research about this particular modem I found out about this defect and promptly let Zito Media's Tier 2 and management know about this. They Brushed it off and I was told that is not an issues with there network and the modem is fine.

So I as quickly as possible downgraded my speed back to the 200Mbps/10Mbps service which they then provided me the previous modem that I had and the issue for the time being was resolved.
Fast forward to July 2022. Zito Media had a promotion for 1Gbps/20Mbps service for $68 a month. I took this offer only if it could be agreed upon that if the service was not satisfactory i could switch back to the previous speed. It was stated that was not an issues so we moved forward with the upgrade. The tech was out the next day. who brought out a Hitron Coda 4589 Which I promptly told him that this modem would give me issues and I wanted another one. He said how do you know this and that they have been having problem after problem with 1Gig service.

He quickly called another tech out to which I explained the Chipset issues to. He had the most Flabbergasted look. I printed off the List of Modems that were affected by this defect which he took and went out to his truck picked out one that was not affected by the defect. they spent about 2 hours troubleshooting and getting a boot file for this modem. after all was said and done I have had great internet connection and speeds since. No loss of signal or channels. Pings times are great for cable <30ms most days. :)

What the ISP has done with this particular information is null at this point.

I hope this post finds you well and I appreciate the time you gave to me.
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Philip
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Post by Philip »

Thanks for sharing, this is really helpful.

I do remember the Puma 6 chipset issues, but that came out like 5 years ago. I thought companies moved on from those affected models, interesting. I am sure this info will help others with troubleshooting!
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