CAX80 problems

[jbtaco2002]

When you buy one of these at this price point, there's a certain expectation that it will just work. set it up once and pretty much forget about it.

That has NOT been the case for me as pretty much on a daily basis, one or all of my Wi-Fi devices will report "Connected, no internet". i log into the router admin, it says ISP cable connection is good, all LED's solid, so what's up? Sometimes it's almost like clockwork, 24 hours after a modem power cycle, things stop working again.

most of the time it is just my Android phone(PixelXL), it'll be the only device not working. i have reset network settings in the phone, rebooted phone Cycle Wi-fi, switch between 2.4 and 5GHz.... nothing. only thing that fixes it is rebooting the modem, which makes no sense when every other device connected at the time is working fine.

i "feel" like there's some DNS lease issue because most times those fields are all zeros, and it should be populated. Clicking renew or release lease does nothing.

i am on Cox in San Diego, and this device is on their compatibility list, but i think should be removed.

going to try a factory reset on the router, already updated router FW ... past my 30 days for return so stuck with this paperweight.

i might go back to the C7800, but switched to this new fancy CAX80 because the other was a monster! so big!

thanks for any help or advice, i'm at my whit's end with this CAX80.

JB

(NOTE: posted this previously in hte wrong forum, thanks)

[jbtaco2002]

When you buy one of these at this price point, there's a certain expectation that it will just work. set it up once and pretty much forget about it.

That has NOT been the case for me as pretty much on a daily basis, one or all of my Wi-Fi devices will report "Connected, no internet". i log into the router admin, it says ISP cable connection is good, all LED's solid, so what's up? Sometimes it's almost like clockwork, 24 hours after a modem power cycle, things stop working again.

most of the time it is just my Android phone(PixelXL), it'll be the only device not working. i have reset network settings in the phone, rebooted phone Cycle Wi-fi, switch between 2.4 and 5GHz.... nothing. only thing that fixes it is rebooting the modem, which makes no sense when every other device connected at the time is working fine.

i "feel" like there's some DNS lease issue because most times those fields are all zeros, and it should be populated. Clicking renew or release lease does nothing.

i am on Cox in San Diego, and this device is on their compatibility list, but i think should be removed.

going to try a factory reset on the router, already updated router FW ... past my 30 days for return so stuck with this paperweight.

i might go back to the C7800, but switched to this new fancy CAX80 because the other was a monster! so big!

thanks for any help or advice, i'm at my whit's end with this CAX80.

JB

(NOTE: posted this previously in hte wrong forum, thanks)

[plemans]

Its only the Pixel having the issue? 

If so, I'd be looking at the pixel specifically. If you search google for "pixel xl wifi disconnecting" there's a ton of reports on it. 

[jbtaco2002]

only occassionally is it just the phone. but last night every device on my network lost internet at the same time, yet wi-fi still connected, all LEDs solid indicating no ISP issues outwardly.

i reboot it, and everything is good for 24 hours usually, then problems start again. it's like the wi-fi router internally looses touch with the cable modem portion.

debating on just buying seperate modem and router now.

so right now, i looked at the "advanced", Internet port, Connection status, and every field is 0.0.0.0, and lease obtained/expired fields all blank. this is what i feel the problem is since i do seem to have an issue every day ~ 24 hours from a reboot...

why are these fields blank?

[plemans]

Do you have a screen snip of the cable connections page and the modem logs? 

If the wifi is connected but showing "connected, no internet" and you don't have an address from the ISP, then it could be a modem/isp/line issue. 

[jbtaco2002]

snip attached, what from the logs would be relevant or helpful? i attached one entry that's concerning to me since it recurs every 15 minutes or so...

thanks for your help!

[jbtaco2002]

the other snip

[jbtaco2002]

EVENT LOGS:

Time	Priority	Description
Tue Sep 15 10:13:35 2020	Warning (5)	Dynamic Range Window violation
Tue Sep 15 10:13:35 2020	Warning (5)	RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Mon Sep 14 19:00:04 2020	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Mon Sep 14 18:16:07 2020	Notice (6)	DS profile assignment change. DS Chan ID: 32; Previous Profile: 2; New Profile: 2 3.;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Mon Sep 14 17:26:01 2020	Warning (5)	Dynamic Range Window violation
Mon Sep 14 17:26:01 2020	Warning (5)	RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Mon Sep 14 17:25:58 2020	Critical (3)	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Mon Sep 14 17:25:58 2020	Notice (6)	DS profile assignment change. DS Chan ID: 32; Previous Profile: 1 2; New Profile: 2.;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Mon Sep 14 17:14:19 2020	Notice (6)	DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2.;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Mon Sep 14 17:13:16 2020	Notice (6)	TLV-11 - unrecognized OID;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Mon Sep 14 17:13:16 2020	Warning (5)	DHCP WARNING - Non-critical field invalid in response ;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:00:53 1970	Notice (6)	Honoring MDD; IP provisioning mode = IPv4
Thu Jan 1 00:00:44 1970	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 9 06:48:18 2020	Critical (3)	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:00:44 1970	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Tue Sep 8 21:04:34 2020	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:00:44 1970	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:00:52 1970	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:00:44 1970	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 6 22:07:34 2020	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 6 22:07:28 2020	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 6 22:07:26 2020	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 6 22:02:35 2020	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 6 22:01:57 2020	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 6 22:01:35 2020	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 6 22:01:09 2020	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 6 22:01:08 2020	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:00:44 1970	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 6 21:48:32 2020	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:01:00 1970	Critical (3)	DHCP FAILED - Discover sent, no offer received;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:00:53 1970	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:00:44 1970	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 6 21:39:55 2020	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:00:44 1970	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 6 21:19:58 2020	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 6 21:19:56 2020	Critical (3)	No Ranging Response received - T3 time-out;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Thu Jan 1 00:00:44 1970	Critical (3)	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 6 21:10:52 2020	Critical (3)	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 6 21:05:27 2020	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 6 20:58:44 2020	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:3e:8a:a0;CMTS-MAC=00:38:df:9a:01:d1;CM-QOS=1.1;CM-VER=3.1;

[plemans]

t3 errors and the dynamic window violation tend to indicate a line issue. 

The 2 other screen shots weren't the cable connections page. When you first log into the CAX80 from your computer, click on the internet/cable connection icon 

[plemans]

if there's any splitters, attenuators, amplifiers in line, I'd remove them. 

[jbtaco2002]

there is a 6db attenuator right at the cable input to the CAX80. i can remove and see what happens as far an the connection is concerned.

i happened to try speed test with and without the attenuator inline and it was drastically slower with it removed, so i put it back.

thanks

[dadabunchie]

I have similar issues.  I believe the DHCP server gets hung and has a bunch of other issues as noted in another thread.  I'm on Spectrum but my WiFi devices get kicked off and when the Gateway reboots its config is all messed up.  I have custom settings for most everything on the Gateway.  This happened when Spectrum had outages but it still happens without an outage.

Definitely shouldn't happen with a flagship device in this price range.

my 2 cents

[FURRYe38]

Has a factory reset been performed since installation? 

What kind of configurations are you using? 

Have the ISP check the signal and line quality UP to the modem. 
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. 

I would file a support ticket regarding this. 

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@dadabunchie wrote:

I have similar issues.  I believe the DHCP server gets hung and has a bunch of other issues as noted in another thread.  I'm on Spectrum but my WiFi devices get kicked off and when the Gateway reboots its config is all messed up.  I have custom settings for most everything on the Gateway.  This happened when Spectrum had outages but it still happens without an outage.

Definitely shouldn't happen with a flagship device in this price range.

my 2 cents

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[vkdelta]

pls post the Connection table (showing Downstream and upstream) power table.

[jbtaco2002]

@vkdelta 

apologies in advance, i no longer have the CAX80 connected, i got rid of that POS after 3-4 more reboots required to fix my home network the other day. with my wife and I working from home, this is not acceptable.

i bought a c7800, and it is working flawlessly.

there is something wrong with the CAX80, given the issues i had even registering it with Cox cable, requiring multiple phone calls with their support to get it working and activated correctly.

the c7800 activated and worked out of the box. set up in 5 minutes...

i'd gladly send the defective unit back so you can troubleshoot the root cause, but i am past my 30 day return window on amazon for a refund, though i suppose still in the warranty window? IDK, i'm just glad to be done with that thing. expected the BEST and literlly got the worst.

John

[BEB7474]

Did you ever get an answer? I noticed the same on mine.

[FURRYe38]

Has a factory reset been performed since installation? 

What kind of configurations are you using? 

Have the ISP check the signal and line quality UP to the modem. 
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. 

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@BEB7474 wrote:
Did you ever get an answer? I noticed the same on mine.

---

[trpeople]

I am on my second Netgear CAX80 modem/router. I have had the same issues as you and I am also in San Diego on COX.

I have all devices in my home connected to the internet on both the 2.4ghz & 5ghz bands. Everything works except for my Samsung S20 Plus. I have gone though ALL the reset options via Samsung, but they say it's the Modem/Router. 

Did you find anything to fix this? I am still searching Netgear with no sign of how to contact then directly. Chat redirects in a circle back to here and I cannot find a telephone number to get a technician.

[FURRYe38]

Is the TV the only devices having problems? 

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@trpeople wrote:

I am on my second Netgear CAX80 modem/router. I have had the same issues as you and I am also in San Diego on COX.

I have all devices in my home connected to the internet on both the 2.4ghz & 5ghz bands. Everything works except for my Samsung S20 Plus. I have gone though ALL the reset options via Samsung, but they say it's the Modem/Router. 

Did you find anything to fix this? I am still searching Netgear with no sign of how to contact then directly. Chat redirects in a circle back to here and I cannot find a telephone number to get a technician.

---

[dadabunchie]

---

I @trpeople wrote:

I am on my second Netgear CAX80 modem/router. I have had the same issues as you and I am also in San Diego on COX.

I have all devices in my home connected to the internet on both the 2.4ghz & 5ghz bands. Everything works except for my Samsung S20 Plus. I have gone though ALL the reset options via Samsung, but they say it's the Modem/Router. 

Did you find anything to fix this? I am still searching Netgear with no sign of how to contact then directly. Chat redirects in a circle back to here and I cannot find a telephone number to get a technician.

---

I also had this issue with both a Galaxy S10+ and Galaxy S20+ phone and I think its related to the DHCP server on the CAX80.  On your phone try using the Phone MAC address instead of a Randomized MAC address. Also try clearing out devices on the CAX80 device list.  It seems to only affect WiFi 6 client devices.

My 2 cents

[trpeople]

Thank you for your 2 cents. It helped, kind of... I still need to do a New System Setup everytime. I reboot the modem, but so far Internet works on Samsung Galaxy S20 Plus.

I did this:
Disable MAC Address Randomization in Android 10
Open the Settings app.
Select Network and Internet.
Select WiFi.
Connect to the UT wireless network (UT Open or EDUROAM)
Tap the gear icon next to the current wifi connection.
Select Advanced.
Select Privacy.
Select "Use device MAC"

[jbtaco2002]

i tried the phone mac address thing too, nothing really fixed the problem with the CAX-80.

the "FIX" in the end was putting the CAX-80 back in the box and soon to be listed on ebay or craigslist.

i am running the c7800 now without a single issue for a month... its big and ugly but it works unlike the CAX-80. i'm on gigblast internet with COX and i get the same speeds with both docsis 3.1 wifi routers, so unless Netgear can find a solution for the much prettier CAX-80, its just junk as far as i'm concerned.

GL to you all!

JB

---

@trpeople wrote:
Thank you for your 2 cents. It helped, kind of... I still need to do a New System Setup everytime. I reboot the modem, but so far Internet works on Samsung Galaxy S20 Plus.

I did this:
Disable MAC Address Randomization in Android 10
Open the Settings app.
Select Network and Internet.
Select WiFi.
Connect to the UT wireless network (UT Open or EDUROAM)
Tap the gear icon next to the current wifi connection.
Select Advanced.
Select Privacy.
Select "Use device MAC"

---

[FURRYe38]

Just wondering if disabling of AX mode on the CAX changed any behaviors...

@vkdelta 

---

@trpeople wrote:
Thank you for your 2 cents. It helped, kind of... I still need to do a New System Setup everytime. I reboot the modem, but so far Internet works on Samsung Galaxy S20 Plus.

I did this:
Disable MAC Address Randomization in Android 10
Open the Settings app.
Select Network and Internet.
Select WiFi.
Connect to the UT wireless network (UT Open or EDUROAM)
Tap the gear icon next to the current wifi connection.
Select Advanced.
Select Privacy.
Select "Use device MAC"

---

[dadabunchie]

---

@FURRYe38 wrote:

Just wondering if disabling of AX mode on the CAX changed any behaviors...

@vkdelta 

---

@trpeople wrote:
Thank you for your 2 cents. It helped, kind of... I still need to do a New System Setup everytime. I reboot the modem, but so far Internet works on Samsung Galaxy S20 Plus.

I did this:
Disable MAC Address Randomization in Android 10
Open the Settings app.
Select Network and Internet.
Select WiFi.
Connect to the UT wireless network (UT Open or EDUROAM)
Tap the gear icon next to the current wifi connection.
Select Advanced.
Select Privacy.
Select "Use device MAC"

---

---

Fundamentally I think there are things wrong with this unit, 1) DHCP server hangs, 2) Entire unit reboots when ISP Carrier drops Modem signal, 3) Post reboot the modem randomly resets all settings to default, 4) Logs are lost after reboot/reset.  It's a big mess but when it works its fairly stable.

my 2 cents

[FURRYe38]

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@dadabunchie wrote:

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Fundamentally I think there are things wrong with this unit, 1) DHCP server hangs, What FW are you using?

Something I have not need since getting mine earlier this year.

2) Entire unit reboots when ISP Carrier drops Modem signal,

This is by design. I asked about this. 

3) Post reboot the modem randomly resets all settings to default,

I saw this as well and should have been fixed. 

4) Logs are lost after reboot/reset. Something I'm not sure about if the logs are kept after a reboot or even if you enable the logs for 5 secnds then select save logs again may capture the logs. I believe most routers and modems clear the logs on any reboot though. 

my 2 cents

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[dadabunchie]

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@FURRYe38 wrote:

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@dadabunchie wrote:

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Fundamentally I think there are things wrong with this unit, 1) DHCP server hangs, What FW are you using?

Something I have not need since getting mine earlier this year.

2) Entire unit reboots when ISP Carrier drops Modem signal,

This is by design. I asked about this. 

3) Post reboot the modem randomly resets all settings to default,

I saw this as well and should have been fixed. 

4) Logs are lost after reboot/reset. Something I'm not sure about if the logs are kept after a reboot or even if you enable the logs for 5 secnds then select save logs again may capture the logs. I believe most routers and modems clear the logs on any reboot though. 

my 2 cents

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The unit is  on FW V1.1.0.41 and cable FW V1.02.08

my 2 cents

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