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mdob07

Cable Modem Help!

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I know this is a bit off topic but I figure someone on here might be able to help me. We've been having a lot of issues with our Spectrum internet for the past few weeks, and even before that it would intermittently go out maybe once a month or so but nothing like it is doing recently. I've been checking the signal levels on my Netgear modem and the downstream seems to be within spec, but the upstream power seems to be way off. On a speedtest from my wired desktop the pings are always high and speeds are not close to what they are supposed to be. Not sure if anyone here is experienced with cable modems and can offer any suggestions. I'd like to make sure the issue isn't on my end before calling Spectrum out to investigate. I have changed out the main splitter on the side of my house, as well as tested with a cable straight from the new and old splitter into my modem but neither seemed to make any difference to either speed or signal strength. I will be working from home for the foreseeable future and need my internet to work. Here is the signal info from my modem, anyone see anything that stands out to them? 

Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 561000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security Enable BPI+
IP Provisioning Mode Override MDD IPv6 only
 
Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 17 561000000 Hz 3.2 dBmV 40.0 dB 0 0
2 Locked QAM256 1 459000000 Hz 1.7 dBmV 40.0 dB 0 0
3 Locked QAM256 2 465000000 Hz 1.8 dBmV 40.1 dB 0 0
4 Locked QAM256 3 471000000 Hz 2.2 dBmV 40.2 dB 0 0
5 Locked QAM256 4 477000000 Hz 2.6 dBmV 40.2 dB 0 0
6 Locked QAM256 5 483000000 Hz 2.3 dBmV 40.1 dB 0 0
7 Locked QAM256 6 489000000 Hz 1.6 dBmV 39.9 dB 0 0
8 Locked QAM256 7 495000000 Hz 1.3 dBmV 39.9 dB 0 0
9 Locked QAM256 8 507000000 Hz 2.2 dBmV 38.0 dB 0 0
10 Locked QAM256 9 513000000 Hz 2.2 dBmV 40.1 dB 0 0
11 Locked QAM256 10 519000000 Hz 2.4 dBmV 40.0 dB 0 0
12 Locked QAM256 12 531000000 Hz 3.0 dBmV 40.1 dB 0 0
13 Locked QAM256 13 537000000 Hz 3.0 dBmV 40.1 dB 0 0
14 Locked QAM256 14 543000000 Hz 2.9 dBmV 40.0 dB 0 0
15 Locked QAM256 15 549000000 Hz 3.0 dBmV 39.9 dB 0 0
16 Locked QAM256 16 555000000 Hz 3.2 dBmV 39.9 dB 0 0
17 Locked QAM256 21 585000000 Hz 3.8 dBmV 40.8 dB 0 0
18 Locked QAM256 22 591000000 Hz 4.0 dBmV 40.9 dB 0 0
19 Locked QAM256 23 597000000 Hz 4.0 dBmV 40.9 dB 0 0
20 Locked QAM256 24 603000000 Hz 4.2 dBmV 40.8 dB 0 0
21 Locked QAM256 25 609000000 Hz 4.3 dBmV 40.9 dB 0 0
22 Locked QAM256 26 615000000 Hz 4.5 dBmV 41.4 dB 0 0
23 Locked QAM256 27 621000000 Hz 4.6 dBmV 41.4 dB 0 0
24 Locked QAM256 31 645000000 Hz 5.0 dBmV 41.4 dB 0 0
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 17 5120 Ksym/sec 17600000 Hz 51.0 dBmV
2 Locked ATDMA 18 5120 Ksym/sec 24000000 Hz 51.0 dBmV
3 Locked ATDMA 19 5120 Ksym/sec 30400000 Hz 51.0 dBmV
4 Locked ATDMA 20 5120 Ksym/sec 36800000 Hz 51.0 dBmV
5 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
 
Current System Time: Mon Mar 23 19:42:51 2020

 

WWFI17Yl.png

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Posted (edited)

Spectrum could say it is the modem if you own it. (Likely not since you did not include logs which modem owners typically get.)  Power levels are too high upstream generally speaking, but need the modem model to be certain.  However lack of correctables points to network overload.

 

Typically a new cable run to your house is the best solution if more than a few years old. Alternate best solution is to trim a few inches of the end af each cable. Alternatively a newer modem may sometimes solve the issue since they typically cover more of the less used frequencies.

Edited by dkyeager
lack of correctables

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If your area is covered by a recommended or ordered stay at home/quarantine and/or school closures/spring break it could be overloaded by more gamers and work at home folks. Switching to Spectrum business might then be the answer. Typically you get higher priority and quicker service (not true with other business offerings such as wowway).Spectrum business rates have fallen a lot in recent times.

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4 minutes ago, dkyeager said:

Spectrum could say it is the modem if you own it. (Likely not since you did not include logs which modem owners typically get.)  Power levels are too high upstream generally speaking, but need the modem model to be certain.

 

Typically a new cable run to your house is the best solution if more than a few years old. Alternate best solution is to trim a few inches of the end af each cable. Alternatively a newer modem may sometimes solve the issue since they typically cover more of the less used frequencies.

Modem is a Netgear CM600. Its only about 1.5 -2 years old as my old Arris modem didn't last very long. I do own the Modem. The cable run from the pole to the house is about 25-26 years old, so I may start by requesting a new line. It did feel very brittle when I was messing with it while changing out the splitter. I may order some ends from Amazon and try to re-terminate them myself. I reset the event log earlier when I was messing with everything and so far its still empty. I'll check again in the morning. Seems like everytime it goes out its the uplink that is failing. The downlink will connect but it will sit on uplink trying to establish and eventually reboot and start over. This has been going on for 5-6 months now but progressive seems to be getting worse in the last few weeks. Sometimes I can pull power and let it sit for a few minutes and then it will successfully connect, and sometimes it goes at least a day before I can get it to connect. 

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1 hour ago, mdob07 said:

 

Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 561000000 Hz Locked
Connectivity State OK Operational
Boot State OK Operational
Security Enable BPI+
IP Provisioning Mode Override MDD IPv6 only
 
Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 17 561000000 Hz 3.2 dBmV 40.0 dB 0 0
2 Locked QAM256 1 459000000 Hz 1.7 dBmV 40.0 dB 0 0
3 Locked QAM256 2 465000000 Hz 1.8 dBmV 40.1 dB 0 0
4 Locked QAM256 3 471000000 Hz 2.2 dBmV 40.2 dB 0 0
5 Locked QAM256 4 477000000 Hz 2.6 dBmV 40.2 dB 0 0
6 Locked QAM256 5 483000000 Hz 2.3 dBmV 40.1 dB 0 0
7 Locked QAM256 6 489000000 Hz 1.6 dBmV 39.9 dB 0 0
8 Locked QAM256 7 495000000 Hz 1.3 dBmV 39.9 dB 0 0
9 Locked QAM256 8 507000000 Hz 2.2 dBmV 38.0 dB 0 0
10 Locked QAM256 9 513000000 Hz 2.2 dBmV 40.1 dB 0 0
11 Locked QAM256 10 519000000 Hz 2.4 dBmV 40.0 dB 0 0
12 Locked QAM256 12 531000000 Hz 3.0 dBmV 40.1 dB 0 0
13 Locked QAM256 13 537000000 Hz 3.0 dBmV 40.1 dB 0 0
14 Locked QAM256 14 543000000 Hz 2.9 dBmV 40.0 dB 0 0
15 Locked QAM256 15 549000000 Hz 3.0 dBmV 39.9 dB 0 0
16 Locked QAM256 16 555000000 Hz 3.2 dBmV 39.9 dB 0 0
17 Locked QAM256 21 585000000 Hz 3.8 dBmV 40.8 dB 0 0
18 Locked QAM256 22 591000000 Hz 4.0 dBmV 40.9 dB 0 0
19 Locked QAM256 23 597000000 Hz 4.0 dBmV 40.9 dB 0 0
20 Locked QAM256 24 603000000 Hz 4.2 dBmV 40.8 dB 0 0
21 Locked QAM256 25 609000000 Hz 4.3 dBmV 40.9 dB 0 0
22 Locked QAM256 26 615000000 Hz 4.5 dBmV 41.4 dB 0 0
23 Locked QAM256 27 621000000 Hz 4.6 dBmV 41.4 dB 0 0
24 Locked QAM256 31 645000000 Hz 5.0 dBmV 41.4 dB 0 0
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 17 5120 Ksym/sec 17600000 Hz 51.0 dBmV
2 Locked ATDMA 18 5120 Ksym/sec 24000000 Hz 51.0 dBmV
3 Locked ATDMA 19 5120 Ksym/sec 30400000 Hz 51.0 dBmV
4 Locked ATDMA 20 5120 Ksym/sec 36800000 Hz 51.0 dBmV
5 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
7 Not Locke Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
 
 

Don't forget that recycling your modem likely erases useful error logs.

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Just now, mdob07 said:

Modem is a Netgear CM600. Its only about 1.5 -2 years old as my old Arris modem didn't last very long. I do own the Modem. The cable run from the pole to the house is about 25-26 years old, so I may start by requesting a new line. It did feel very brittle when I was messing with it while changing out the splitter. I may order some ends from Amazon and try to re-terminate them myself. I reset the event log earlier when I was messing with everything and so far its still empty. I'll check again in the morning. Seems like everytime it goes out its the uplink that is failing. The downlink will connect but it will sit on uplink trying to establish and eventually reboot and start over. This has been going on for 5-6 months now but progressive seems to be getting worse in the last few weeks. Sometimes I can pull power and let it sit for a few minutes and then it will successfully connect, and sometimes it goes at least a day before I can get it to connect. 

Oh, and I forgot to add once my modem is running for more than a day it usually drops to just one uplink channel. I have to power cycle to get bonded uplink channels back. When its using bonded uplink channels the light on the front is green, but turns to amber if in single channel mode. 

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8 minutes ago, mdob07 said:

Oh, and I forgot to add once my modem is running for more than a day it usually drops to just one uplink channel. I have to power cycle to get bonded uplink channels back. When its using bonded uplink channels the light on the front is green, but turns to amber if in single channel mode. 

Yes one of my cm600s was doing that. Fixed by have cable replaced.   My SNR downstream is around 39dB, upstream is about 44.5dB

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20 minutes ago, mdob07 said:

Its only about 1.5 -2 years old as my old Arris modem didn't last very long.

I'm on my second Arris SB8200. First one would randomly decide to stop passing through IPv4 traffic. 

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10 minutes ago, dkyeager said:

Yes one of my cm600s was doing that. Fixed by have cable replaced.   My SNR downstream is around 39dB, upstream is about 44.5dB

Yeah, I think I'll make that my next step. I pretty much eliminated everything in my house by connecting straight to the splitter outside. I couldn't find an adapter to connect two cables together or I would connected straight to their cable on the side of my house. When our house was build it was just a small regional Cable Co, that was then bought out by Insight,  which merged with Time Warner, which merged to create Spectrum... I have no idea what kind of shape their infrastructure is in around here. 

Does anyone know if they typically charge to run a new line from the pole to my house? Or is that considered their responsibility? I don't know if they consider the demarc to be my splitter or the junction box on the pole. 

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1 minute ago, mdob07 said:

Yeah, I think I'll make that my next step. I pretty much eliminated everything in my house by connecting straight to the splitter outside. I couldn't find an adapter to connect two cables together or I would connected straight to their cable on the side of my house. When our house was build it was just a small regional Cable Co, that was then bought out by Insight,  which merged with Time Warner, which merged to create Spectrum... I have no idea what kind of shape their infrastructure is in around here. 

Does anyone know if they typically charge to run a new line from the pole to my house? Or is that considered their responsibility? I don't know if they consider the demarc to be my splitter or the junction box on the pole. 

No charge here in Ohio.  I had the route carefully planned to avoid crab apple roots. Needs to be marked with special flags. They cut straight thru. I had an arborist look at it and then Spectrum paid for two years of tree fertilizing.

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1 minute ago, dkyeager said:

No charge here in Ohio.  I had the route carefully planned to avoid crab apple roots. Needs to be marked with special flags. They cut straight thru. I had an arborist look at it and then Spectrum paid for two years of tree fertilizing.

Nice, mine will be easy as its all overhead. 50-60 ft run max accounting for the vertical drop on the side of my house. 

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14 minutes ago, mdob07 said:

Nice, mine will be easy as its all overhead. 50-60 ft run max accounting for the vertical drop on the side of my house. 

Its a little further apart than the picture makes it look, I had to use scenery mode to get it all in frame and it gave it a wide angle lens effect. Decent night picture quality in low light for my S20 Ultra. 

Wt1loCS.jpg

hj994D5.jpg

 

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1 hour ago, dkyeager said:

  However lack of correctables points to network overload.

Just saw this; before I turned it off for the first time to switch to the cable I ran out my back door it was showing a high number of both correctables and uncorrectables on all of the channels. Still showing 0 for now though. We'll see what it looks like in the morning. 

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5 hours ago, mdob07 said:

Just saw this; before I turned it off for the first time to switch to the cable I ran out my back door it was showing a high number of both correctables and uncorrectables on all of the channels. Still showing 0 for now though. We'll see what it looks like in the morning. 

Just wait until you have some criticals in tbe log before you call them as well.  Take screen shots of criticals in log and power levels above 50db. Tell them to check logs before you reboot and offer to send them your screen shots showing the logs with critical and above 50dB upload power levels. Tell them how old your cable is.  Your goal is to get them to send a tech out to your place. Good luck!!

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Heres a look at the logs this morning: 

Time Priority Description
2020-03-23, 23:13:03 Error (4) Missing BP Configuration Setting TLV Type: 17.8;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:01:5c:76:c8:6c;CM-QOS=1.1;CM-VER=3.0;
2020-03-23, 23:13:03 Error (4) Missing BP Configuration Setting TLV Type: 17.9;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:01:5c:76:c8:6c;CM-QOS=1.1;CM-VER=3.0;
2020-03-23, 23:08:17 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:01:5c:76:c8:6c;CM-QOS=1.0;CM-VER=3.0;
2020-03-23, 23:08:10 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2020-03-23, 23:07:38 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2020-03-23, 23:07:35 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:01:5c:76:c8:6c;CM-QOS=1.1;CM-VER=3.0;
2020-03-23, 23:07:35 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:01:5c:76:c8:6c;CM-QOS=1.1;CM-VER=3.0;
2020-03-23, 23:07:34 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:01:5c:76:c8:6c;CM-QOS=1.1;CM-VER=3.0;
2020-03-23, 23:07:33 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:01:5c:76:c8:6c;CM-QOS=1.1;CM-VER=3.0;
2020-03-23, 23:07:32 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:01:5c:76:c8:6c;CM-QOS=1.1;CM-VER=3.0;
2020-03-23, 23:07:29 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:01:5c:76:c8:6c;CM-QOS=1.1;CM-VER=3.0;
2020-03-23, 23:07:28 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:01:5c:76:c8:6c;CM-QOS=1.1;CM-VER=3.0;
2020-03-23, 23:07:22 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:01:5c:76:c8:6c;CM-QOS=1.1;CM-VER=3.0;
2020-03-23, 23:07:22 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:01:5c:76:c8:6c;CM-QOS=1.1;CM-VER=3.0;
2020-03-23, 23:07:20 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:01:5c:76:c8:6c;CM-QOS=1.1;CM-VER=3.0;
2020-03-23, 23:07:19 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:01:5c:76:c8:6c;CM-QOS=1.1;CM-VER=3.0;
2020-03-23, 23:07:16 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:01:5c:76:c8:6c;CM-QOS=1.1;CM-VER=3.0;
2020-03-23, 23:07:12 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=b0:39:56:04:84:40;CMTS-MAC=00:01:5c:76:c8:6c;CM-QOS=1.1;CM-VER=3.0;
Time Not Established Notice (6) Overriding MDD IP initialization parameters; IP provisioning mode = IPv6

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I had a similar issue with my cable internet about 15 years ago, but only during the day, and not every day.. Comcast was out several times trying to figure it out. Would start/end almost the same time every day, I was recording modem logs and ping times..

Turned out to be the run coming into the house.. the wire was deteriorated to the point where it was ok until the sun hit it! So on sunny days, it was failing from sunrise to sunset.. cloudy days and at night, it was fine. Blew my mind but a new cable into the house fixed it.

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4 minutes ago, mikejeep said:

I had a similar issue with my cable internet about 15 years ago, but only during the day, and not every day.. Comcast was out several times trying to figure it out. Would start/end almost the same time every day, I was recording modem logs and ping times..

Turned out to be the run coming into the house.. the wire was deteriorated to the point where it was ok until the sun hit it! So on sunny days, it was failing from sunrise to sunset.. cloudy days and at night, it was fine. Blew my mind but a new cable into the house fixed it.

I''m hoping that fixes this issue. The cable from the pole feels really thin and brittle and has a perforation on it like it was a Siamese cable that was pulled apart.  

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2 hours ago, mikejeep said:

I had a similar issue with my cable internet about 15 years ago, but only during the day, and not every day.. Comcast was out several times trying to figure it out. Would start/end almost the same time every day, I was recording modem logs and ping times..

Turned out to be the run coming into the house.. the wire was deteriorated to the point where it was ok until the sun hit it! So on sunny days, it was failing from sunrise to sunset.. cloudy days and at night, it was fine. Blew my mind but a new cable into the house fixed it.

Ha, that's oddly very similar circumstances to a scenario I had in my IT support job several years back in TN.  At that time the state agency I was employed through had moved to these large Lexmark MFP printers on roller carts, and one of the small county offices was having a semi-consistent issue with faxes not coming through.  Our contracted Lexmark service support came onsite, could find no issue with the hardware.  Local telco was contacted, they came onsite and both brought their own device to test with as well as hooked up the old standalone fax back in the storage room, and everything tested fine there.  Both angles were pointing fingers at each other.  Finally someone in state office got in contact with higher level management on both sides and arranged for them to come onsite together along with me so we could all try and figure out what was going on.

Turns out the newer technology in the MFP required a higher voltage threshold somehow coming off the 'ring generator' downline in the phone system, they finally traced the issue to said ring generator in the equipment that serviced the block area this office was in.  The ring generator hadn't gone bad, but it had deteriorated just enough so as not to provide the proper power through the line to trigger the MFP to pick up on/recognize it had an incoming fax attempt.  Soon as they replaced the appropriate piece of hardware, all was resolved.

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After almost 45 minutes of on hold, got in touch with a rep at Spectrum. Should have a tech out here in the morning to look at it. I got a picture of the gear at the pole, the line on the left with the loop is the one feeding my house. 

b9Iu8mI.jpg

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After almost 45 minutes of on hold, got in touch with a rep at Spectrum. Should have a tech out here in the morning to look at it. I got a picture of the gear at the pole, the line on the left with the loop is the one feeding my house.


Hopefully it's something outside, otherwise you might have to wait awhile..

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