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Intermittent Cable connection packet loss for 3+ years, ISP unable to fix it.

Hello everyone.


At this point I'm pulling my hair out as my ISP/Cable provider has been unable (or unwilling) to fix my issues that I've been having for 3 years now (Pretty much since ive been a subscriber to their services.


I need some guidance of some expert that actually knows coaxial cable networks more than my current Internet provider does.




The problem is pretty straightforward; A dozen times a day my connection starts to screw up, upstream seems to become very, very poor.

I first started to notice it with VOIP calls (Teamspeak) where I could hear everyone without a single hickup, but when the packet loss attack started to occur everyone started to hear me with pretty much distortion only.

Everything indoors has been replaced or tested numerous times by my ISP and myself, cables, modems, the connection point.

Without me intervening the attacks can take 15 up to 45 minutes, depending on how unlucky i am.




So i've started to analyze the situation and to get some sort of clues. So far after all these years I have discovered the following:


- As soon as the packet loss attack occurs, the second I powercycle my modem and reconnect, my connection is stable again.

If i do not do this, the attack will endure for 15-45 minutes on average.

- It doesnt appear to be weather related, as it occurs both in Winter and summer, rain or long periods of dryness. It makes no difference.

- It doesnt happen all the time, there have been days where it only occured once, or not at all.

- The packet loss attacks are not something random it seems, there seems to be some sort of pattern to it. (Will attach a screenshot in this post)

Regarding the patterns, it does seem like the intervals can become more narrow than other times, like the problem occurs every half an hour rather than an hour etc

Also, as you can see in the screenshot, sometimes on the 'predicted' intervals i sometimes observe a single packet loss event and everything is fine after that. As if the problem isnt able to always properly manifest and escalate.


(I have bought a WeMo Switch, it is a power switch with Wifi support. I have a Virtual machine running 24/7 now and when more than 3 instances of packet loss within a short timeframe is detected, my WeMo automatically powercycles the modem 2 floors down.)



I supplemented this post with a screenshot of how the issue looks like in pingplotter.


I simply have no more clue what to do, and the problem seems to be so obvious as we have multiple clues and discoveries that should've made it way easier to deal with the problem. My ISP seems to be ignoring whatever i throw at them and think its a signal issue. But IMHO its way too structured to be a random signal fluke.


HELP! I need an expert! Has anyone ever seen something as weird as this?

Could it be a problem with their CMTS? Ive asked numberous times whether that device was not buggy or otherwise damaged, they told me the CMTS operated properly.



Modem: Cisco EPC3208 (Altho it doesnt matter, same crap happens on my old Arris modem. Definately an issue outside of the house.


edit: I know, ISP's put custom firmware on them, hence why i am even unable to reach the device unless i reboot it with the coaxial cable unplugged, but someone must know why i can fix my packet loss issues by rebooting the modem, and why it has such a steady interval pattern to it. I find it hard to believe this is a random fluctuation on a damaged cable as weather conditions dont matter, and the pattern is way too structured for it to be some random distortion on the line.


Someone must be able to exclude possible causes based on this information :/

I suspect either a faulty amplifier or CMTS, be it hardware or software issue. But im by no means an expert.

VIP Blue

Definitely wrong community to

You mentioned no technology used. Neither kind of cable connection nor type of WAN device on your's side. Thus expect no valuable answer ...

Community Member

Modem: Cisco EPC3208 (Docsis

Modem: Cisco EPC3208 (Docsis 3.0)

Router: Irrelevant


40/4Mbit EuroDocsis 2.0 connection.


1 Meter coaxial cable to the first inlet, no splitters or anything used.

VIP Blue

The EPC3208 devices have

The EPC3208 devices have firmware customized for particular provider. It's why expert on EPC3208 manufactured for provider A may not help you with EPC3208 manufactured for provider B. And it's why Cisco provide no support for those devices and why there's even no volunteer's community dedicated to this class of devices.

So little chance anyone will help you here. Only provider in question may help you.


Community Member

Thanks for the reply. But i

Thanks for the reply. But i am not seeking support for my particular modem, and since the exact same occurances happen on my old Arris modem it is not  particularly a modem issue either way.

VIP Blue

Someone must be able to

Someone must be able to exclude possible causes based on this information :/

Sure. I wish you will find such person here, but I will not bet on it.


Community Member

Well, thanks for responding

Well, thanks for responding anyway. I had to try.


Perhaps one day an expert or someone who has experienced the same thing will know what the cause was and can pass on that knowledge to me, so i can spank my ISP.

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