Another CBR750 and Comcast/Xfiniity ISP Service Issue

Guru - Experienced User

Jun 02, 2023

What speed package do you pay for? 800Mbps or 1Gb?

Power levels are good. A few odd Correctables but nothing major. Mostly zeros. Any Criticals, Errors or Warnings seen in the modems event logs has to be reviewed by the ISP and resolved by them.

How many RBS are deployed?
What is the size of your home? Sq Ft?
What is the distance between the router and 📡 satellite(s)? 30 feet or more is recommended in between RBR📡 and RBS🛰️ to begin with depending upon building materials when wirelessly connected.
https://kb.netgear.com/31029/Where-should-I-place-my-Orbi-satellite ‌‌🛰️

What channels are you using? Auto? Try setting manual channel 1, 6 or 11 on 2.4Ghz and 40 to 48 channel on 5Ghz.
Any Wifi Neighbors near by? If so, how many?

Any of the following enabled? Armor, Smart Parental Controls or Circle, Traffic Meter. If so, disable all these.

If you haven't factory reset since the FW update, this would be the next step. A complete pull of the power adapters for a period of time after the factory reset then walk thru the setup wizard and setup from scratch with a wired PC and web browser. Recommend setting the default DHCP IP address pool range to the following after applying and a factory reset: 192.168.#.100 to 192.168.#.200.
https://kb.netgear.com/24089/How-do-I-specify-the-pool-of-IP-addresses-assigned-by-my-Nighthawk-rout...
I would power OFF the ISP modem for 1 minute. Factory reset the Orbi router and power it off. Power ON the ISP modem and let it sync. Then power ON the Orbi router and walk thru the setup wizard again using a wired PC and a web browser.
Press the back reset button for 15 seconds then release.
https://kb.netgear.com/31486/How-do-I-reset-my-Orbi-system-to-factory-default-settings
https://kb.netgear.com/000062081/How-do-I-erase-the-configuration-settings-on-my-Orbi-WiFi-System

Might reduce the power from 100% to 50% on the RBR for wifi. For that size of home, and two RBS, you could get away with having 1 RBS but for two, i'd reduce the power.

Lets do a full on factory reset and setup from scratch. Don't enable Armor.

After the reset, give it say 10 minutes, then copy and pastes the cable connections status and event logs page for me again.

FURRYe38
Guru - Experienced User
Jun 02, 2023
What speed package do you pay for? 800Mbps or 1Gb?

angeloh

Aspirant

Jun 02, 2023

I initially subscribed for 800Mb/s speed from Xfinity. On their app, I see two different values. In one place I see 800Mb/s and in another I see 1000Mb/s. The modem syncs at just under 1200Mb/s download and around 17Mb/s upload.

FURRYe38

Guru - Experienced User

Jun 02, 2023

Ok. Just know that last year CC/XF was said to stop support of 1Gb plan and split into 800Mpbs and 1.2Gb. Found that others with the CBR had issues when the ISP upgraded them to 1.2Gb. NG has been working with the ISP since last year on this. Technically the CBR modem side can handle the 1.2Gb input, but the LAN side won't due to the 1000Mpbs LAN ports. Been recommended if users get 1.2Gb, downgrade to 800Mpbs for the CBR.

After your factory reset and setup from scratch this weekend please repost both cable connections and event log pages.

I have passed your post thread on to NG for review.

angeloh

Aspirant

Jun 04, 2023

I factory reset and applied all suggested configurations yesterday evening. A few observations from my side:

1. After the factory reset the modem sychronized at 800 Mb/s

2. As I was configuring LAN and other options the modem had to reboot a few times. It subsequently synchronized at 1000Mb/s and eventually at 1200Mb/s

3. I experienced an issue with some of my devices not obtaining DHCP leases after reboot. I had to restart the modem 3 times until it eventually responded to DHCP requests from all of my devices connected to the network. Both 2.4GHz as well as 5GH devices were affected by this.

I have an appointment with Xfinity today - I hope to get the speed set back to 800 Mb/s. Needs to run for a few days before I can declare it is stable.

Current cable diagnostics:

Cable Diagnostic

Status: Good

Action: Your setup looks fine. If you are still experience an internet issue, the Netgear Cable Knowledge Base can provide additional troubleshooting info.

Internet Access: Green

Downstream Status: Green

Upstream Status: Green

Refresh Save Cable Diagnostic Info

Advanced Information

Frequency Start Value

This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.

Starting Frequency

Startup Procedure

Procedure	Status	Comment
Acquire Downstream Channel	471000000 Hz	Locked
Connectivity State	Ok	Operational
Boot State	Ok	Operational
Security	Enabled	BPI+
IP Provisioning Mode	Honor MDD	honorMdd(4)

Downstream Bonded Channels

Channel	Lock Status	Modulation	Channel ID	Frequency	Power	SNR	Correctables	Uncorrectable
1	Locked	QAM 256	1	453000000 Hz	0.0 dBmV	43.3 dB	11	0
2	Locked	QAM 256	2	459000000 Hz	0.0 dBmV	40.9 dB	0	0
3	Locked	QAM 256	3	465000000 Hz	0.0 dBmV	43.3 dB	0	0
4	Locked	QAM 256	4	471000000 Hz	0.0 dBmV	43.3 dB	1	0
5	Locked	QAM 256	5	477000000 Hz	0.0 dBmV	40.9 dB	0	0
6	Locked	QAM 256	6	483000000 Hz	0.0 dBmV	40.9 dB	0	0
7	Locked	QAM 256	7	489000000 Hz	0.0 dBmV	40.9 dB	0	0
8	Locked	QAM 256	8	495000000 Hz	0.0 dBmV	40.9 dB	0	0
9	Locked	QAM 256	9	501000000 Hz	-0.2 dBmV	40.9 dB	0	0
10	Locked	QAM 256	10	507000000 Hz	0.0 dBmV	40.9 dB	0	0
11	Locked	QAM 256	11	513000000 Hz	0.0 dBmV	40.9 dB	7	0
12	Locked	QAM 256	12	519000000 Hz	0.0 dBmV	40.3 dB	0	0
13	Locked	QAM 256	13	525000000 Hz	0.2 dBmV	43.3 dB	0	0
14	Locked	QAM 256	14	531000000 Hz	0.2 dBmV	40.9 dB	0	0
15	Locked	QAM 256	15	537000000 Hz	0.2 dBmV	40.9 dB	0	0
16	Locked	QAM 256	16	543000000 Hz	0.2 dBmV	40.9 dB	0	0
17	Locked	QAM 256	17	549000000 Hz	0.5 dBmV	40.9 dB	0	0
18	Locked	QAM 256	18	555000000 Hz	0.5 dBmV	43.3 dB	0	0
19	Locked	QAM 256	19	561000000 Hz	0.7 dBmV	43.3 dB	0	0
20	Locked	QAM 256	20	567000000 Hz	0.5 dBmV	40.9 dB	0	0
21	Locked	QAM 256	21	573000000 Hz	0.7 dBmV	40.9 dB	0	0
22	Locked	QAM 256	22	579000000 Hz	0.7 dBmV	40.9 dB	0	0
23	Locked	QAM 256	23	585000000 Hz	0.7 dBmV	40.3 dB	0	0
24	Locked	QAM 256	24	591000000 Hz	0.7 dBmV	40.9 dB	0	0
25	Locked	QAM 256	25	597000000 Hz	0.7 dBmV	40.9 dB	0	0
26	Locked	QAM 256	26	603000000 Hz	1.2 dBmV	40.9 dB	0	0
27	Locked	QAM 256	27	609000000 Hz	1.5 dBmV	40.9 dB	0	0
28	Locked	QAM 256	28	615000000 Hz	1.5 dBmV	40.9 dB	0	0
29	Locked	QAM 256	29	621000000 Hz	1.2 dBmV	40.9 dB	0	0
30	Locked	QAM 256	30	627000000 Hz	1.2 dBmV	40.3 dB	0	0
31	Locked	QAM 256	31	633000000 Hz	1.2 dBmV	40.9 dB	0	0
32	Locked	QAM 256	32	639000000 Hz	1.5 dBmV	40.9 dB	0	0

Upstream Bonded Channels

Channel	Lock Status	US Channel Type	Channel ID	Symbol Rate	Frequency	Power
1	Locked	ATDMA	4	5120 Ksym/sec	16400000 Hz	37.8 dBmV
2	Locked	ATDMA	3	5120 Ksym/sec	22800000 Hz	38.5 dBmV
3	Locked	ATDMA	2	5120 Ksym/sec	29200000 Hz	39.0 dBmV
4	Locked	ATDMA	1	5120 Ksym/sec	35600000 Hz	39.8 dBmV
5	Not Locked	N/A	Unknown	0 Ksym/sec	0 Hz	0.0 dBmV
6	Not Locked	N/A	Unknown	0 Ksym/sec	0 Hz	0.0 dBmV
7	Not Locked	N/A	Unknown	0 Ksym/sec	0 Hz	0.0 dBmV
8	Not Locked	N/A	Unknown	0 Ksym/sec	0 Hz	0.0 dBmV

Downstream OFDM Channels

Channel	Lock Status	Modulation/Profile ID	Channel ID	Frequency	Power	SNR/MER	Active Subcarrier Number Range	Unerrored Codewords	Correctable Codewords	Uncorrectable Codewords
1	Locked	3	193	957000000 Hz	-0.4 dBmV	42.5 dB	148~3947	0	0	0
2	Not Locked	0	0	0 Hz	0.0 dBmV	0.0 dB	0~4095	0	0	0

Upstream OFDMA Channels

Channel	Lock Status	Modulation/Profile ID	Channel ID	Frequency	Power
1	Not Locked	0	0	0 Hz	0.0 dBmV
2	Not Locked	0	0	0 Hz	0.0 dBmV

Current System Time: Sun Jun 4 07:23:46 2023

System Up Time 12:42:23

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Another CBR750 and Comcast/Xfiniity ISP Service Issue