Random disconnects: C7000v2 (Nighthawk AC1900)

Question

Throughout the day, I experience random disconnects from the internet for roughly 30 seconds to 1 minute at a time. This will happen seemingly randomly, whether my computer is using the connection through ethernet, or my girlfriend is up late watching TikTok. I have contacted my ISP and gone through all of the regular troubleshooting, and I was hoping that someone could point me in the right direction!

My ISP is Breezeline, and I have contacted them repeatedly about this issue, since it has been ongoing since I got their service and the Netgear modem in April. They have issued signal resets, gone through the process of unplugging and reconnection my modem, and even sent out a tech a little over a week ago. The tech said that nothing was wrong on Breezeline's end, and the only thing he did was replace a corroded connection on the outside of the buildings. I attempted to show him the error logs, and he said that he didn't understand what the logs were saying. Either way, a tech came out and could not fix the issue.

I'm not sure if this is an ISP issue or a modem issue, but I'm hoping that someone here can help me narrow down the root cause and solution. Below, I have attached my down/upstream channels and the event logs from the most recent times it occurred (twice in the last hour). Please let me know if you need any other information, and thank you in advance for your help!

Time	Priority	Description
2025-6-9, 20:22:52	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=54:07:7d:06:43:c8;CMTS-MAC=70:1f:53:99:e2:40;CM-QOS=1.1;CM-VER=3.0;
2025-6-9, 20:22:03	Warning (5)	DHCP WARNING - Non-critical field invalid in response ;CM-MAC=54:07:7d:06:43:c8;CMTS-MAC=70:1f:53:99:e2:40;CM-QOS=1.1;CM-VER=3.0;
2025-6-9, 20:22:00	Notice (6)	Honoring MDD; IP provisioning mode = IPv4
2025-6-9, 20:21:47	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=54:07:7d:06:43:c8;CMTS-MAC=70:1f:53:99:e2:40;CM-QOS=1.1;CM-VER=3.0;
2025-6-9, 20:21:14	Critical (3)	Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=54:07:7d:06:43:c8;CMTS-MAC=70:1f:53:99:e2:40;CM-QOS=1.1;CM-VER=3.0;
2025-6-9, 19:54:47	Notice (6)	WiFi Interface [wl0] set to Channel 11 (Side-Band Channel:N/A) - Reason:INTERFERENCE
2025-6-9, 19:48:54	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=54:07:7d:06:43:c8;CMTS-MAC=70:1f:53:99:e2:40;CM-QOS=1.1;CM-VER=3.0;
2025-6-9, 19:48:05	Warning (5)	DHCP WARNING - Non-critical field invalid in response ;CM-MAC=54:07:7d:06:43:c8;CMTS-MAC=70:1f:53:99:e2:40;CM-QOS=1.1;CM-VER=3.0;
2025-6-9, 19:48:01	Notice (6)	Honoring MDD; IP provisioning mode = IPv4
2025-6-9, 19:47:28	Critical (3)	Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=54:07:7d:06:43:c8;CMTS-MAC=70:1f:53:99:e2:40;CM-QOS=1.1;CM-VER=3.0;
2025-6-9, 19:47:25	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=54:07:7d:06:43:c8;CMTS-MAC=70:1f:53:99:e2:40;CM-QOS=1.1;CM-VER=3.0;
2025-6-9, 19:46:35	Warning (5)	DHCP WARNING - Non-critical field invalid in response ;CM-MAC=54:07:7d:06:43:c8;CMTS-MAC=70:1f:53:99:e2:40;CM-QOS=1.1;CM-VER=3.0;
2025-6-9, 19:46:31	Notice (6)	Honoring MDD; IP provisioning mode = IPv4
2025-6-9, 19:46:17	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=54:07:7d:06:43:c8;CMTS-MAC=70:1f:53:99:e2:40;CM-QOS=1.1;CM-VER=3.0;
2025-6-9, 19:45:44	Critical (3)	Unicast Ranging Received Abort Response - Re-initializing MAC;CM-MAC=54:07:7d:06:43:c8;CMTS-MAC=70:1f:53:99:e2:40;CM-QOS=1.1;CM-VER=3.0;

Startup Procedure

Procedure	Status	Comment
Acquire Downstream Channel	333000000 Hz	Locked
Connectivity State	OK	Operational
Boot State	OK	Operational
Security	Disabled	Disabled
IP Provisioning Mode	Honor MDD	honorMdd(4)

Downstream Bonded Channels

Channel	Lock Status	Modulation	Channel ID	Frequency	Power	SNR	Correctables	Uncorrectables
1	Locked	QAM256	6	333000000 Hz	3.9 dBmV	42.7 dB	29	82
2	Locked	QAM256	1	303000000 Hz	4.1 dBmV	42.9 dB	16	54
3	Locked	QAM256	2	309000000 Hz	4.1 dBmV	42.9 dB	27	44
4	Locked	QAM256	3	315000000 Hz	4.1 dBmV	42.7 dB	29	121
5	Locked	QAM256	4	321000000 Hz	4 dBmV	42.6 dB	24	51
6	Locked	QAM256	5	327000000 Hz	4 dBmV	42.6 dB	20	50
7	Locked	QAM256	7	339000000 Hz	3.8 dBmV	42.2 dB	17	51
8	Locked	QAM256	8	345000000 Hz	3.7 dBmV	42.5 dB	14	54
9	Locked	QAM256	9	351000000 Hz	3.8 dBmV	42.7 dB	17	56
10	Locked	QAM256	10	357000000 Hz	3.6 dBmV	42.5 dB	13	59
11	Locked	QAM256	11	363000000 Hz	3.6 dBmV	42.6 dB	16	58
12	Locked	QAM256	12	369000000 Hz	3.7 dBmV	42.7 dB	17	51
13	Locked	QAM256	13	375000000 Hz	3.7 dBmV	42.7 dB	29	91
14	Locked	QAM256	14	381000000 Hz	3.8 dBmV	42.9 dB	11	56
15	Not Locked	Unknown	0	0 Hz	0.0 dBmV	0.0 dB	0	0
16	Not Locked	Unknown	0	0 Hz	0.0 dBmV	0.0 dB	0	0
17	Not Locked	Unknown	0	0 Hz	0.0 dBmV	0.0 dB	0	0
18	Not Locked	Unknown	0	0 Hz	0.0 dBmV	0.0 dB	0	0
19	Not Locked	Unknown	0	0 Hz	0.0 dBmV	0.0 dB	0	0
20	Not Locked	Unknown	0	0 Hz	0.0 dBmV	0.0 dB	0	0
21	Not Locked	Unknown	0	0 Hz	0.0 dBmV	0.0 dB	0	0
22	Not Locked	Unknown	0	0 Hz	0.0 dBmV	0.0 dB	0	0
23	Not Locked	Unknown	0	0 Hz	0.0 dBmV	0.0 dB	0	0
24	Not Locked	Unknown	0	0 Hz	0.0 dBmV	0.0 dB	0	0

Upstream Bonded Channels

Channel	Lock Status	US Channel Type	Channel ID	Symbol Rate	Frequency	Power
1	Locked	ATDMA	1	5120 Ksym/sec	36800000 Hz	47.5 dBmV
2	Locked	ATDMA	2	5120 Ksym/sec	30400000 Hz	48 dBmV
3	Locked	ATDMA	3	5120 Ksym/sec	24000000 Hz	47 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

Kitsap · Answer

Duckware is a solid resource.&nbsp; You might find some ideas here:&nbsp;https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html&nbsp;

FURRYe38 · Answer

Any Criticals, Errors or Warnings seen in the event logs needs to be reviewed and resolved by the ISP. Indicates a signal issue on the ISP line up to the modem.
&nbsp;
Correctables and un-correctables that should be mostly zeros.Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly.Be sure there are no coax cable line splitters in the between the modem and ISP service box.&nbsp;Be sure your using good quality RG6 coax cable up to the modem.&nbsp;Start with removing any amplifiers, signal attenuators, or splitters from the coax.From there check the line for kinks, damage, moisture in the line.Check the connectors for improperly made ends, foil touching the copper coax line, loose connections, bad/old/cheap connectors, or corroded connections. Replace them if you do.Be sure to power OFF the modem for 1 minute then back ON.https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Modems/m-p/1530376#M12853https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-routerhttps://www.duckware.com/tech/solving-intermittent-cable-modem-issues.htmlhttps://highspeed.tips/docsis-events/
&nbsp;
SgtHartman​&nbsp;

FURRYe38 · Answer

Let us know how it turns out.&nbsp;

SgtHartman · Answer

Thanks for the resource! It seems incredibly helpful!

SgtHartman · Answer

Thank you for all of the helpful information! I actually contacted my ISP again, and they're sending a technician today (surprisingly). I'm going to relay all of the information that you and Kitsap gave me to them, so thanks!

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Random disconnects: C7000v2 (Nighthawk AC1900)

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