Connection periodically dropping

This has been happening for months--the connection cuts out for around 30 seconds while the modem reconnects. You can see the modem's not connected by visiting the status page or watching as all the lights on the modem except power flash off and come back on as it reconnects. I originally had my own modem and replaced with a Spectrum supplied modem and that didn't help. A technician has also come out and redid some wiring but that didn't help either. The modem was originally in a surge protector and now a UPS but still has issues. Other devices on the same power source have never had problems.


  1. 43016-apartment complex
  2. Internet
  3. Arris TM1602AP2
  4. Ubiquiti Edgerouter X
  5. Package is 100Mbps/10Mbps and speedtest/latency  is always fine when it's working
  6. It's hard to track every disconnect but they seem to have happened multiple times tonight. I usually notice them in the evening but I'm not home during the day and the modem log doesn't have much detail
  7. Not sure about wiring--the modem connects through a splitter that has the other port capped (this was put in to slightly bump upstream power)
  8. Seems like this possibly started happening when packages were switched to 100 Mbps from 60 but we've only lived here since June. I never noticed issues with the 60 Mbps package
  9. It doesn't seem to matter whether the internet connection is idle or in use

Modem pages


Re: Connection periodically dropping

Just like in this post the times in the error log don't correspond to restarts. This seems unique to the TM1602 as my SB6121 I was using before seemed to be logging things when the connection dropped


You can see it's only been up 19 minutes (just restarted) and there's nothing in the log


Re: Connection periodically dropping

See if a factory reset will get the home channel off 699 mHz... I think it's getting trashed by your 4G LTE phone, probabably on T mobile...


Spectrum Employee

Re: Connection periodically dropping

You may have networking hardware issues too, likely do.  But there's two things that I question here from a physical plant stand point.


Do you have cable boxes too or is this only an internet modem?

-> If there's cable boxes,

then we need to come out and re-arrange the splitters or add a good-quality unity-gain (no loss, no gain) amp.

-> If there's no cable boxes,

then why the heck is your Rx/Forward/Downstream power only -3's dBmV?!  What's needed is to remove whatever splitters are there.  If you have splitters that go to nothing -- just open ports on splitters or random unused wires attached -- then that's just a source of noise (which negatively affects internet, b/c it mostly affect low frequencies, which are used for upstream)


3 dB difference between the lowest frequency of the upstream/return/Tx (19.4 MHz) and the highest frequency of the upstream/return/Tx (37 MHz) is a bit too much tilt.

Thus, there's some maintenance tech fine-tuning to do here as well.  A 3 dB tilt isn't going to cause this issue, but it's indicative that a street amp or LE is (or even the node's fiber optic) is a bit offset somewhere on the outside plant.  Think of it like an early warning sign, not a cause of the problem but something we'd like to get fixed.  In other words, it's "non-impacting", but has room to be fixed/improved.





My postings on this site are my own, off-the-clock, and don’t necessarily represent TWC’s/Charter's strategies or opinions.

Re: Connection periodically dropping

Couldn't figure out how to factory reset this model but I'll play around more tonight. We use AT&T and Verizon but I suppose somewhere in a neighboring unit could have lots of T-Mobile gear. The equipment is in a spare bedroom


Re: Connection periodically dropping

Here's the reason for the splitter

The tech that came out replaced it with a higher quality one and capped the open port. Only a single modem--no cable boxes. I don't think there are any other splitters on the way to the outside of the apartment but I don't have a lot of visibility into the wiring.

What's meant by networking hardware issues? It's the same stack working for a year at a different address and a very similar setup to my parents house. The connection works flawlessly--it just drops when the modem periodically resets.


Re: Connection periodically dropping

It reset again and this showed up in the log this time

1/11/2018 9:06730402003TLV-11 - Illegal Set operation failed;CM-MAC=2c:7e:81:c3:18:20;CMTS-MAC=00:01:5c:8b:6c:64;CM-QOS=1.1;CM-VER=3.0;