Forum Discussion

Aspirant

Sep 28, 2022

CAX30 - losing signal every few minutes

MODEM-ROUTER purchased from costco in May 2022. Problem started 2 weeks ago and keeps happening every few minutes. I work from home and can't have any type of teams or zoom meeting without losing s...

FURRYe38

Guru - Experienced User

Sep 28, 2022

What Firmware version is currently loaded?

Happens on wired devices as well?

What channels are you using? Auto? Try Auto and 48 on 5Ghz. Or 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?

Please post a copy and paste of the modems connection status and event log page.
https://kb.netgear.com/30007/How-do-I-obtain-the-cable-connection-information-from-a-NETGEAR-cable-modem-modem-router
https://kb.netgear.com/30008/How-do-I-view-or-clear-the-event-logs-on-my-NETGEAR-cable-modem-or-modem-router

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.
Be sure your using good quality RG6 coax cable up to the modem.
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#M12853
https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router?article=24311
https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html

mikaelderderian

Aspirant

Sep 29, 2022

Thank you so much for the support. I just changed the channels as suggested and issue continues.

Note that I have 3 WIFI neighbors - their network names are very different.

Cable type and setup has not been changed since may when it was working perfectly (issue started couple weeks ago)

Hardware Version	V1.01
Firmware Version	V1.4.10.10
Cable Firmware Version	V1.04.09

Here is the data from the cable connection tab.

Cable Connection

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

<tabindex=-1>Startup Procedure</tabindex=-1>

Procedure	Status	Comment
Acquire Downstream Channel	675000000 Hz	Locked
Connectivity State	OK	Registration Complete
Boot State	OK	Operational
Security	Enabled	BPI+
IP Provisioning Mode	Honor MDD	IPv4 only

<tabindex=-1>Downstream Bonded Channels</tabindex=-1>

Channel	Lock Status	Modulation	Channel ID	Frequency	Power	SNR	Correctables	Uncorrectabables
1	Locked	256 QAM	31	675000000 Hz	-2.-5 dBmV	40.4 dB	482	19
2	Locked	256 QAM	1	489000000 Hz	0.8 dBmV	42.9 dB	0	0
3	Locked	256 QAM	2	495000000 Hz	0.7 dBmV	42.8 dB	0	0
4	Locked	256 QAM	3	501000000 Hz	0.5 dBmV	42.6 dB	0	0
5	Locked	256 QAM	4	507000000 Hz	0.5 dBmV	42.7 dB	0	0
6	Locked	256 QAM	5	513000000 Hz	0.8 dBmV	42.9 dB	0	0
7	Locked	256 QAM	6	519000000 Hz	0.3 dBmV	42.6 dB	0	0
8	Locked	256 QAM	7	525000000 Hz	0.0 dBmV	42.4 dB	0	0
9	Locked	256 QAM	8	531000000 Hz	0.3 dBmV	42.6 dB	0	0
10	Locked	256 QAM	9	537000000 Hz	0.3 dBmV	42.7 dB	0	0
11	Locked	256 QAM	10	543000000 Hz	0.-3 dBmV	41.8 dB	0	0
12	Locked	256 QAM	11	549000000 Hz	0.-5 dBmV	42.0 dB	0	0
13	Locked	256 QAM	12	555000000 Hz	0.-4 dBmV	42.2 dB	0	0
14	Locked	256 QAM	13	561000000 Hz	0.-1 dBmV	42.3 dB	0	0
15	Locked	256 QAM	14	567000000 Hz	0.-9 dBmV	41.2 dB	0	0
16	Locked	256 QAM	15	573000000 Hz	-1.-4 dBmV	41.4 dB	0	0
17	Locked	256 QAM	16	585000000 Hz	0.-8 dBmV	41.9 dB	0	0
18	Locked	256 QAM	17	591000000 Hz	-1.-5 dBmV	41.2 dB	0	0
19	Locked	256 QAM	18	597000000 Hz	-1.-6 dBmV	41.4 dB	0	0
20	Locked	256 QAM	19	603000000 Hz	-1.-7 dBmV	41.5 dB	0	0
21	Locked	256 QAM	20	609000000 Hz	-1.-9 dBmV	41.4 dB	0	0
22	Locked	256 QAM	21	615000000 Hz	-2.0 dBmV	41.2 dB	0	0
23	Locked	256 QAM	22	621000000 Hz	-2.-4 dBmV	41.1 dB	0	0
24	Locked	256 QAM	23	627000000 Hz	-2.-4 dBmV	40.8 dB	0	0
25	Locked	256 QAM	24	633000000 Hz	-2.-6 dBmV	38.3 dB	0	0
26	Locked	256 QAM	25	639000000 Hz	-2.-9 dBmV	37.3 dB	0	0
27	Locked	256 QAM	26	645000000 Hz	-2.-7 dBmV	41.0 dB	0	0
28	Locked	256 QAM	27	651000000 Hz	-2.-8 dBmV	41.0 dB	0	0
29	Locked	256 QAM	28	657000000 Hz	-3.-2 dBmV	40.7 dB	0	0
30	Locked	256 QAM	29	663000000 Hz	-3.-2 dBmV	40.7 dB	0	0
31	Locked	256 QAM	30	669000000 Hz	-2.-9 dBmV	40.8 dB	0	0
32	Not Locked	Unknown	0	0 Hz	0.0 dBmV	0.0 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	1	5120 Ksym/sec	21900000 Hz	42.3 dBmV
2	Locked	ATDMA	2	5120 Ksym/sec	28300000 Hz	42.8 dBmV
3	Locked	ATDMA	3	5120 Ksym/sec	34700000 Hz	44.3 dBmV
4	Locked	ATDMA	4	5120 Ksym/sec	39500000 Hz	45.8 dBmV
5	Not Locked	Unknown	0	0 Ksym/sec	0 Hz	0 dBmV
6	Not Locked	Unknown	0	0 Ksym/sec	0 Hz	0 dBmV
7	Not Locked	Unknown	0	0 Ksym/sec	0 Hz	0 dBmV
8	Not Locked	Unknown	0	0 Ksym/sec	0 Hz	0 dBmV

<tabindex=-1>Downstream OFDM Channels</tabindex=-1>

Channel	Channel ID	Indicator	Subcarrier Zero Frequency	Active Subcarrier Number Range	Total Codewords	Uncorrectable Codewords
1	32	Non-Primary	611.6 MHz	1348 ~ 2747	192376317	0
2	0	Other	0 MHz	0 ~ 0	0	0

Channel	UpstreamIsMuted	Ranging Status	Subcarrier Zero Frequency	Active Subcarrier Number Range	Symbols Per Frame	Tx Power
1		Other	0 MHz	0 ~ 0	0	0 dBmV
2		Other	0 MHz	0 ~ 0	0	0 dBmV

FURRYe38

Guru - Experienced User

Sep 29, 2022

Well power is a bit on the low side but with in specs.

Zeros for Correct and un-correctables.

Has a factory reset and setup from scratch been performed.

Try reducing the WiFi power on the modem from 100% to 50%. Under Advanced Tab/Advanced Settings/Wireless Settings

Can you find out what channels your Neighbors are using?

Set channels 1 and 40 or 11 and 48 or 149 for the wifi radios.

Please post a copy of the Event Logs as well here.

mikaelderderian

Aspirant

Sep 29, 2022

Thanks again.

I did change to 50% but issue continues - same for the channels.

Manufacturing reset has been done last week.

I don't have an easy way to get the channel from my neighbors...

Here is the log event:

Time	Priority	Description
2022-09-29 11:44:28	Warning (5)	REG-RSP-MP Mismatch Between Calculated Value for P1.6hi Compared to CCAP Provided Value;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:01:5c:78:c6:6e;CM-QOS=1.1;CM-VER=3.1;
2022-09-29 11:44:23	Notice (6)	DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2.;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:01:5c:78:c6:6e;CM-QOS=1.1;CM-VER=3.1;
2022-09-29 11:44:22	Notice (6)	TLV-11 - unrecognized OID;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:01:5c:78:c6:6e;CM-QOS=1.1;CM-VER=3.1;
2022-09-29 11:44:21	Warning (5)	DHCP WARNING - Non-critical field invalid in response ;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:01:5c:78:c6:6e;CM-QOS=1.1;CM-VER=3.1;
1970-01-01 00:00:30	Notice (6)	Honoring MDD; IP provisioning mode = IPv4
1970-01-01 00:00:24	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
1970-01-01 00:00:32	Critical (3)	No Ranging Response received - T3 time-out;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:01:5c:78:c6:6e;CM-QOS=1.1;CM-VER=3.1;
1970-01-01 00:00:25	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
1970-01-01 00:00:32	Critical (3)	No Ranging Response received - T3 time-out;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:01:5c:78:c6:6e;CM-QOS=1.1;CM-VER=3.1;
1970-01-01 00:00:25	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
1970-01-01 00:00:32	Critical (3)	No Ranging Response received - T3 time-out;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:01:5c:78:c6:6e;CM-QOS=1.1;CM-VER=3.1;
1970-01-01 00:00:25	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2022-09-22 17:39:58	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:01:5c:78:c6:6e;CM-QOS=1.1;CM-VER=3.1;
1970-01-01 00:00:32	Critical (3)	No Ranging Response received - T3 time-out;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:01:5c:78:c6:6e;CM-QOS=1.1;CM-VER=3.1;
1970-01-01 00:00:24	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2022-09-22 14:59:21	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:01:5c:78:c6:6e;CM-QOS=1.1;CM-VER=3.1;
1970-01-01 00:00:29	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
2022-09-21 08:49:51	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=80:cc:9c:df:26:18;CMTS-MAC=00:01:5c:78:c6:6e;CM-QOS=1.1;CM-VER=3.1;

FURRYe38
Guru - Experienced User
Sep 29, 2022
You some Criticals that the ISP needs to review and resolve.

I would have the ISP online with you while checking there logs and signal if they can see the modem go off line...