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Connections started dropping after speed upgrade

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Regular Visitor

Connections started dropping after speed upgrade

I have a NetGear CM600 modem.

Using Netgear Orbi for the router and wifi.

 

I called Comcast and they upgraded me from 100/5 to 600/15

The upgrade happened over the phone, pretty seamless.  Was able to test from the Orbi itself and get the new speeds (tests from the wifi were obviously slower).

 

Thought everything was good, but my internet started dropping every 15-20minutes for a good 2-3 minutes at a time.

 

Since I'm working from home as somany are, I panicked a little.  Couldnt get Comcast back on the phone, but did get them on chat and managed to get them to downgrade me back to 100/5 and things stabilized again.

 

The tech I was chatting with told me the CM600 was only rated up to 250mbps.  That could be, but doesnt sound right, besides that fact that the modem is *supposed* to go up to 900+mbps, Comcasts own "My Device" section says it should work with the 600mbps plan.

 

There is one splitter between the modem and the pole that I can see, but it is on the outsiode of the house.

 

During the outages, continuous pings to the Orbi and the modem (192.168.100.1)  stayed steady, but continuous ping to 8.8.8.8 dropped.

There were a bunch of errors in the cable modem log and there still seem to be errors in the log now even though I'm not losing connection.

These two just repeating constantly:

Time Priority Description
2020-04-17, 16:58:25 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=14:59:c0:5d:dc:10;CMTS-MAC=58:97:bd:98:11:5f;CM-QOS=1.1;CM-VER=3.0;
2020-04-17, 16:58:12 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=14:59:c0:5d:dc:10;CMTS-MAC=58:97:bd:98:11:5f;CM-QOS=1.1;CM-VER=3.0;

 

I did nt think to cut and paste the following info when I was on the upgraded speed, but here is how it reads now while I'm back on 100/5:

Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 651000000 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</tabindex=-1>
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 25 651000000 Hz 8.6 dBmV 37.1 dB 24 0
2 Locked QAM256 9 555000000 Hz 8.4 dBmV 37.6 dB 2 0
3 Locked QAM256 10 561000000 Hz 8.6 dBmV 37.8 dB 2 0
4 Locked QAM256 11 567000000 Hz 8.6 dBmV 37.8 dB 1 0
5 Locked QAM256 12 573000000 Hz 8.2 dBmV 37.6 dB 1 0
6 Locked QAM256 13 579000000 Hz 8.6 dBmV 37.8 dB 0 0
7 Locked QAM256 14 585000000 Hz 8.7 dBmV 37.7 dB 0 0
8 Locked QAM256 15 591000000 Hz 8.4 dBmV 37.6 dB 0 0
9 Locked QAM256 16 597000000 Hz 8.3 dBmV 37.6 dB 1 0
10 Locked QAM256 17 603000000 Hz 8.2 dBmV 37.5 dB 1 0
11 Locked QAM256 18 609000000 Hz 7.9 dBmV 37.4 dB 4 0
12 Locked QAM256 19 615000000 Hz 8.3 dBmV 37.4 dB 6 0
13 Locked QAM256 20 621000000 Hz 8.2 dBmV 37.2 dB 9 0
14 Locked QAM256 21 627000000 Hz 8.4 dBmV 37.4 dB 2 0
15 Locked QAM256 22 633000000 Hz 8.6 dBmV 37.3 dB 11 0
16 Locked QAM256 23 639000000 Hz 8.4 dBmV 37.1 dB 9 0
17 Locked QAM256 24 645000000 Hz 8.1 dBmV 37.2 dB 0 0
18 Locked QAM256 26 657000000 Hz 8.2 dBmV 37.1 dB 0 0
19 Locked QAM256 27 663000000 Hz 8.1 dBmV 36.9 dB 0 0
20 Locked QAM256 28 669000000 Hz 8.2 dBmV 36.8 dB 0 0
21 Locked QAM256 29 675000000 Hz 8.1 dBmV 36.8 dB 0 0
22 Locked QAM256 30 681000000 Hz 8.2 dBmV 36.8 dB 0 0
23 Locked QAM256 31 687000000 Hz 8.3 dBmV 36.8 dB 0 0
24 Locked QAM256 32 693000000 Hz 8.0 dBmV 36.6 dB 0 0
 
<tabindex=-1>Upstream Bonded Channels</tabindex=-1>
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 5 5120 Ksym/sec 36500000 Hz 43.5 dBmV
2 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
3 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
4 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 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

 

My question comes down to: is my modem Cm600 not really cutting it for a 600/15 service? Or do I have some sort of problem with the cable itself or otherwise upstream and should schedule a tech?

 

I dont really know how to interpret the raw data above, but in browsing these posts it seems like there are a few folks out there who do know what they are looking at.  Any help would be appreciated.

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Regular Visitor

Re: Connections started dropping after speed upgrade

modem.jpg

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Diamond Problem Solver

Re: Connections started dropping after speed upgrade

Depending on the market, you’re missing 2 possibly 3 upstream channels. You should have more than 1

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Expert

Re: Connections started dropping after speed upgrade

Have you tried power cycling your modem lately to see if it will pick up more (perhaps cleaner) upstream channels ?



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Regular Visitor

Re: Connections started dropping after speed upgrade

1) I power cycled the mdem during the initial upgrade, but have not power cycled since.  (Rebooted from software, but not full power down)
2) "Depending on the market" - how can I know how many upstream channels I should have?  I'm in Vermont

What would my next step after power cycling be?  Is this something I should be able to communicate to Comcast support?

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Regular Visitor

Re: Connections started dropping after speed upgrade

Full power cycle, same outcomes

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Regular Visitor

Re: Connections started dropping after speed upgrade

@EG I noticed in another of your posts you (maybe several) you say this about the splitters "Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional,"

 

I climbed up on a ladder and took a closer look at the one splitter between the me and the pole (one side goes to the cable modem, other one to the cable TV box).  I disconnected/reconnected the cable modem line and the line to the pole. I'm no expert but I didnt see any signs of corrosion, seemed clean to me.

 

I took a picture but dont think forum lets me post yet.  I's an "Extreme Broadvand Engineering BDS102H" 5-1002MHZ / EMI -130dB

 

It does have 1 "in" label and 2 "out -3.5dB" labels

 

This doesnt sound like it's "bi-directional" as you state.  How important is that?

 

Thanks

 

IMG_7956.jpg

Highlighted
Expert

Re: Connections started dropping after speed upgrade

That's a good quality splitter. They are all bi-directional these days.



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Highlighted
Regular Visitor

Re: Connections started dropping after speed upgrade

I actually managed to get a tech to come out same day.  He cleaned up the wiring outside the house and then went up the pole where he ended up removing a filter of some sort.  Now my error log is clear and I'm getting 4 upstream channels.

 

Startup Procedure
Procedure Status Comment
Acquire Downstream Channel 555000000 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</tabindex=-1>
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 9 555000000 Hz 9.2 dBmV 37.6 dB 0 0
2 Locked QAM256 1 507000000 Hz 8.3 dBmV 35.6 dB 0 0
3 Locked QAM256 2 513000000 Hz 8.2 dBmV 37.3 dB 0 0
4 Locked QAM256 3 519000000 Hz 8.4 dBmV 37.4 dB 0 0
5 Locked QAM256 4 525000000 Hz 8.3 dBmV 37.3 dB 0 0
6 Locked QAM256 5 531000000 Hz 8.8 dBmV 37.7 dB 0 0
7 Locked QAM256 6 537000000 Hz 9.0 dBmV 37.7 dB 0 0
8 Locked QAM256 7 543000000 Hz 9.0 dBmV 37.6 dB 0 0
9 Locked QAM256 8 549000000 Hz 9.0 dBmV 37.4 dB 0 0
10 Locked QAM256 10 561000000 Hz 9.4 dBmV 37.8 dB 0 0
11 Locked QAM256 11 567000000 Hz 9.2 dBmV 37.7 dB 0 0
12 Locked QAM256 12 573000000 Hz 9.1 dBmV 37.5 dB 0 0
13 Locked QAM256 13 579000000 Hz 9.2 dBmV 37.8 dB 0 0
14 Locked QAM256 14 585000000 Hz 9.4 dBmV 37.7 dB 0 0
15 Locked QAM256 15 591000000 Hz 9.2 dBmV 37.6 dB 0 0
16 Locked QAM256 16 597000000 Hz 8.9 dBmV 37.5 dB 0 0
17 Locked QAM256 17 603000000 Hz 8.9 dBmV 38.1 dB 0 0
18 Locked QAM256 18 609000000 Hz 8.8 dBmV 37.9 dB 0 0
19 Locked QAM256 19 615000000 Hz 9.0 dBmV 37.9 dB 0 0
20 Locked QAM256 20 621000000 Hz 9.0 dBmV 37.8 dB 0 0
21 Locked QAM256 21 627000000 Hz 9.2 dBmV 37.9 dB 0 0
22 Locked QAM256 22 633000000 Hz 9.2 dBmV 37.9 dB 0 0
23 Locked QAM256 23 639000000 Hz 9.2 dBmV 37.7 dB 0 0
24 Locked QAM256 24 645000000 Hz 9.0 dBmV 37.5 dB 0 0
 
<tabindex=-1>Upstream Bonded Channels</tabindex=-1>
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 8 5120 Ksym/sec 17300000 Hz 43.3 dBmV
2 Locked ATDMA 5 5120 Ksym/sec 36500000 Hz 43.3 dBmV
3 Locked ATDMA 6 5120 Ksym/sec 30100000 Hz 43.3 dBmV
4 Locked ATDMA 7 5120 Ksym/sec 23700000 Hz 43.3 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: Sat Apr 18 10:30:46 2020
System Up Time: 0:06:19
Highlighted
Expert

Re: Connections started dropping after speed upgrade

Looks good. Happy surfing !!



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I am a Customer Expert volunteering my time to help other customers here in the Forums.
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Highlighted
Diamond Problem Solver

Re: Connections started dropping after speed upgrade

The filter meant you had ingress, your tech fixed. Glad you got it going.

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