Re: How to read/understand the cable diagnostics on the Nighthawk CAX80.

highfalutin60 · ‎2024-05-12

Hardware Version	1.01

Firmware Version	V2.1.5.2

Cable Firmware Version	V1.02.08

When the connection on the Nighthawk CAX80 changes from good to poor due to the downstream status, how can you determine if it is a cable company issue or could it be a device on your network issue.

I reset my Nighthawk CAX80 after the Xfinity repair guy was here to address the poor downstream connection and sporadic connection issues. The service person stated he "made some changes/updates at the box" so that I would not be charged the $100 Xfinity service fee. What those changes are I have no clue.

As I started to add various devices back on to my CAX80, I noticed that the downstream status would change from good to poor sporadically. First, I thought it was my Wyze cameras causing the issue and decided to order 3db Coax Cable Attenuator Pad based on the various test results I was getting yesterday. At the end of the night, I had a poor connection and the downstream was poor, Downstream Power Level: Poor
Downstream power is poor (11.0dBmV). The recommended level is between -10dBmV to 10dBmV.

This morning, I noticed that after turning of my Vizio TV, the connection is now back at good again and when I turn the tv on it goes back to poor. The Vizio is old (2003), came with built in wireless/wired internet. I have noticed that the wireless never finds the Nighthawk or any other router except for the Verizon FIOS router. Attempted to hardwire the tv to the EAX80 right next to it and TV states that it is disconnected. I left the tv plugged into the EAX80 and powered it off. So far everything is ok. I usually have about 10-15 devices online/plugged at one time throughout the house such as Firesticks/airtv, cameras/doorbell, alarm clock, iPhones, iPad, and computers. Just curious what everyone things. I can send the logs to Xfinity, but I know the game and they are going to blame the router and say it's not their problem, they were already here. I can't tell if it is a hardware issue or is Xfinity playing games with me. Any ideas/suggestions would be greatly appreciated. I think I provided enough detail on my environment. Building is a condo 3 floors, and yes, the CAX80 is in the basement, no choice, about 1200sq ft. EAX80 and the Vizio tv is on the 2nd floor. Thank you.

FURRYe38 · ‎2024-05-12

What Firmware version is currently loaded?
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-m...
https://kb.netgear.com/30008/How-do-I-view-or-clear-the-event-logs-on-my-NETGEAR-cable-modem-or-mode...

Power needs to be in between these specs for NG modems and gateways:

https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router

Basements are not recommended places for wifi routers or gateways. Concrete and steel will inhibit good signal travel.

highfalutin60 · ‎2024-05-12

What Firmware version is currently loaded?

Firmware Version	V2.1.5.2

Cable Firmware Version	V1.02.08

Please post a copy and paste of the modems connection status and event log page. (Including the modem connection status 5/11/2024 for comparison)

Cable Connection

Cancel Apply

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:

Downstream Status:

Upstream Status:

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	651 MHz	Locked
Connectivity State	OK	Operational
Boot State	OK	Operational
Security	Enabled	BPI+

Downstream Bonded Channels

Channel	Lock Status	Modulation	Channel ID	Frequency	Power	SNR	Correctables	Uncorrectables
1	Locked	256 QAM	44	651000000 Hz	9.1 dBmV	44.5 dB	0	0
2	Locked	256 QAM	13	465000000 Hz	9.7 dBmV	46.0 dB	0	0
3	Locked	256 QAM	14	471000000 Hz	9.7 dBmV	46.0 dB	0	0
4	Locked	256 QAM	15	477000000 Hz	9.9 dBmV	46.0 dB	0	0
5	Locked	256 QAM	16	483000000 Hz	9.8 dBmV	46.0 dB	0	0
6	Locked	256 QAM	17	489000000 Hz	9.7 dBmV	45.9 dB	0	0
7	Locked	256 QAM	18	495000000 Hz	9.7 dBmV	46.0 dB	0	0
8	Locked	256 QAM	19	501000000 Hz	9.7 dBmV	45.8 dB	0	0
9	Locked	256 QAM	20	507000000 Hz	9.6 dBmV	45.8 dB	0	0
10	Locked	256 QAM	21	513000000 Hz	9.4 dBmV	45.7 dB	0	0
11	Locked	256 QAM	22	519000000 Hz	9.4 dBmV	45.7 dB	0	0
12	Locked	256 QAM	23	525000000 Hz	9.4 dBmV	45.7 dB	0	0
13	Locked	256 QAM	24	531000000 Hz	9.2 dBmV	45.6 dB	0	0
14	Locked	256 QAM	25	537000000 Hz	9.1 dBmV	45.5 dB	0	0
15	Locked	256 QAM	26	543000000 Hz	9.0 dBmV	45.4 dB	0	0
16	Locked	256 QAM	27	549000000 Hz	8.9 dBmV	45.4 dB	0	0
17	Locked	256 QAM	28	555000000 Hz	8.8 dBmV	45.3 dB	0	0
18	Locked	256 QAM	29	561000000 Hz	8.7 dBmV	45.2 dB	0	0
19	Locked	256 QAM	30	567000000 Hz	8.7 dBmV	45.2 dB	0	0
20	Locked	256 QAM	31	573000000 Hz	8.6 dBmV	45.1 dB	0	0
21	Locked	256 QAM	32	579000000 Hz	8.6 dBmV	45.1 dB	0	0
22	Locked	256 QAM	33	585000000 Hz	8.6 dBmV	45.0 dB	0	0
23	Locked	256 QAM	34	591000000 Hz	8.8 dBmV	45.1 dB	0	0
24	Locked	256 QAM	35	597000000 Hz	8.8 dBmV	45.1 dB	0	0
25	Locked	256 QAM	36	603000000 Hz	8.8 dBmV	45.0 dB	0	0
26	Locked	256 QAM	37	609000000 Hz	8.8 dBmV	45.0 dB	0	0
27	Locked	256 QAM	38	615000000 Hz	8.9 dBmV	45.1 dB	0	0
28	Locked	256 QAM	39	621000000 Hz	9.0 dBmV	45.0 dB	0	0
29	Locked	256 QAM	40	627000000 Hz	8.9 dBmV	45.0 dB	0	0
30	Locked	256 QAM	41	633000000 Hz	8.9 dBmV	44.9 dB	0	0
31	Locked	256 QAM	42	639000000 Hz	9.2 dBmV	45.0 dB	0	0
32	Locked	256 QAM	43	645000000 Hz	9.0 dBmV	45.0 dB	0	0

Upstream Bonded Channels

Channel	Lock Status	US Channel Type	Channel ID	Symbol Rate	Frequency	Power
1	Locked	ATDMA	18	5120 Ksym/sec	22800000 Hz	33.0 dBmV
2	Locked	ATDMA	17	5120 Ksym/sec	16400000 Hz	33.0 dBmV
3	Locked	ATDMA	19	5120 Ksym/sec	29200000 Hz	32.8 dBmV
4	Locked	ATDMA	20	5120 Ksym/sec	35600000 Hz	32.8 dBmV
5	Not Locked	Unknown	0	0	0	0.0 dBmV
6	Not Locked	Unknown	0	0	0	0.0 dBmV
7	Not Locked	Unknown	0	0	0	0.0 dBmV
8	Not Locked	Unknown	0	0	0	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	0 ,1 ,2 ,3	193	690000000 Hz	9.58 dBmV	44.6 dB	508 ~ 3587	409167368	161578650	0
2	Locked	0 ,1 ,2 ,3	194	957000000 Hz	3.88 dBmV	42.4 dB	148 ~ 3947	409410584	191372405	0

Upstream OFDMA Channels

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

Extended Upstream Transmit Power

Enable Extended Upstream Transmit Power

Current System Time:Sun May 12 15:35:30 2024

System Up Time:19:43:55

highfalutin60 · ‎2024-05-12

Event Log

Clear Log Refresh

Time	Priority	Description
Sun May 12 05:29:51 2024	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Sun May 12 03:48:07 2024	Notice (6)	CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2.;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Sun May 12 03:43:20 2024	Notice (6)	CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1.;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Sun May 12 02:45:36 2024	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Sun May 12 01:13:00 2024	Notice (6)	CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2.;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Sun May 12 01:10:07 2024	Notice (6)	CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1 2.;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Sun May 12 01:09:59 2024	Notice (6)	CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 2.;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Sun May 12 01:09:12 2024	Notice (6)	CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 1.;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Sat May 11 22:58:28 2024	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Sat May 11 22:35:43 2024	Notice (6)	CM-STATUS message sent. Event Type Code: 4; Chan ID: 193 194; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Sat May 11 22:35:16 2024	Warning (5)	MDD message timeout;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Sat May 11 20:30:59 2024	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Sat May 11 19:53:02 2024	Critical (3)	UCD invalid or channel unusable;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Sat May 11 19:53:00 2024	Notice (6)	DS profile assignment change. DS Chan ID: 33; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Sat May 11 19:52:59 2024	Notice (6)	DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Sat May 11 19:52:34 2024	Notice (6)	TLV-11 - unrecognized OID;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:00:51 1970	Notice (6)	Honoring MDD; IP provisioning mode = IPv6
Thu Jan 1 00:00:45 1970	Critical (3)	UCD invalid or channel unusable;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:00:43 1970	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Sat May 11 16:26:17 2024	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Sat May 11 15:14:12 2024	Critical (3)	UCD invalid or channel unusable;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:00:46 1970	Critical (3)	UCD invalid or channel unusable;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:90:f0:63:04:00;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:00:43 1970	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=94:18:65:a6:1f:63;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

FURRYe38 · ‎2024-05-12

Power levels are too high. I'd get a -6dbm cable coax line attenuator in between the modem and ISP cable line.

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. Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly.

highfalutin60 · ‎2024-05-12

Power levels are too high. I'd get a -6dbm cable coax line attenuator in between the modem and ISP cable line.

Ok - got order the -3db but can return it. Xfinity tech was already here yesterday, and he stated there was nothing wrong with my line/feed coming from the box to my condo unit.

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. Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly.

As for the event log, do I open another ticket with support? Xfinity tech has told me there is no issues so how do I fight this? I can open a ticket and send them the logs but not sure if that will help.

As I stated before, I find it odd that with the Vizio tv turned off, the signal has been great all day. I have been doing spots checks all day. Just wondering if there could be an issue with the board on the tv causing issues on the line.

Thank You for looking at the logs, greatly appreciate it.

FURRYe38 · ‎2024-05-12

All that is on the modem and ISP side. They need to check it out and resolve that.

Be sure your using good quality RG6 coax cable up to the modem.
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.

Nothing we can do here.

highfalutin60 · ‎2024-05-12

All that is on the modem and ISP side. They need to check it out and resolve that.

Be sure your using good quality RG6 coax cable up to the modem.
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.

So basically, you have validated everything I have done so far. I had new RG6 coax cable installed in my condo less than 5 yrs ago.. As for Xfinity, they ran new cable from their box to each of the units maybe <5 years ago per my request because their service sucked so bad. I don't have any amplifiers, attenuators or splitters from the coax. I do have an extender installed on the Xfinity wire but get the same results with or without it. The Xfinity tech provided me with their extender/extra coax because when Xfinity contractor ran the cables in the basement, they only ran it so far and not enough to reach any cable modem box that Xfinity or I have. Hope this makes sense. Moving it would require the extender and more coax run from the basement to the 1st or 2nd floor.

Thank you again.