Intermittent Modem Connection

So no responses from Arris people? How do customers get warranty support ??

We apologize for the inconvenience,  

Could you please confirm your subscribed internet speed plan and the name of your internet service provider?

When the internet connection drops, does it seem like the gateway is rebooting on its own?

Also, when the connection is lost on both Ethernet and Wi-Fi, do the Wi-Fi network names disappear as well?

We recommend checking the cable signal levels within the gateway. If the signal levels are out of the acceptable range, they can lead to the kind of connectivity issues you're experiencing.

When the signal levels are within the recommended range, your modem can maintain a stable, high-quality connection to the internet

Please refer to the link below for instructions on how to check your cable signal levels:

https://arris.my.salesforce-sites.com/consumers/articles/knowledge/G34-G36-Cable-Signal-Levels

The cable signal levels displayed on the interface page reflect the signals being transmitted by your Internet Service Provider (ISP).

If you notice that these signal levels are outside the recommended range, we suggest contacting your ISP to have them reviewed and adjusted accordingly.

While ISPs may have their own approved signal ranges, for this gateway to function properly, the signal levels must align with the acceptable values outlined in the reference article provided.

ISP is Sparklight/CableOne.

Modem loses sync with the ISP, even though it reports all is well with the connection. ISP says SNR drops to zero - the modem’s fault. Modem reports 38dB SNR … apprx +8dBm power levels across 31 channels … yet no real connection and pings to 1.1.1.1 bounce back from modem as “unreachable”.

Modem just sits there fat dumb and happy and dead to the world -- as if there isn’t a problem.  WiFi and Ethernet are unaffected … just nothing getting through the modem.

LOG:

DHCPv6: 72001009-DHCPv6 - No Advertise or Reply Received 1 times 
    02/15/2026 23:56:45    Critical 

DHCPv6: 72001004-DHCPv6 Provision - 10 Retries Attempted with Last attempt at Sun Feb 15 23:47:26 2026 
    02/15/2026 23:56:45    Critical 

DHCPv6: 72001004-DHCPv6 Provision - 9 Retries Attempted with Last attempt at Sun Feb 15 23:42:57 2026 
    02/15/2026 23:47:26    Critical 

UTOPIA: lan.dhcpserver action: old MAC: (Edited private information) IP: 192.168.0.20 VendorClass: android-dhcp-15 
    02/15/2026 23:45:26    Notice 

DHCPv6: 72001004-DHCPv6 Provision - 8 Retries Attempted with Last attempt at Sun Feb 15 23:40:45 2026 
    02/15/2026 23:42:57    Critical 

MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:38:11    Warning
No Ranging Response received - T3 time-out;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:33:00    Critical
Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:32:49    Critical
Ranging Request Retries exhausted;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:32:49    Critical
No Ranging Response received - T3 time-out;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:32:01    Critical
Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:31:48    Critical
Ranging Request Retries exhausted;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:31:48    Critical
No Ranging Response received - T3 time-out;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:26:11    Critical
Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:26:01    Critical
Ranging Request Retries exhausted;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:26:00    Critical
No Ranging Response received - T3 time-out;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:26:00    Critical
CM-STATUS message sent.  Event Type Code: 7; Chan ID: 2; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:25:49    Notice
No Ranging Response received - T3 time-out;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:25:12    Critical
Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:24:59    Critical
Ranging Request Retries exhausted;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:24:59    Critical
No Ranging Response received - T3 time-out;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:19:23    Critical
Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:19:12    Critical
Ranging Request Retries exhausted;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:19:12    Critical
No Ranging Response received - T3 time-out;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:18:28    Critical
Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:18:11    Critical
Ranging Request Retries exhausted;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:18:11    Critical
No Ranging Response received - T3 time-out;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:17:29    Critical
US profile assignment change.  US Chan ID: 9; Previous Profile: 11; New Profile: 12.;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:17:28    Notice
No Ranging Response received - T3 time-out;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:17:27    Critical
US profile assignment change.  US Chan ID: 9; Previous Profile: 10; New Profile: 11.;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 23:17:09    Notice
CM-STATUS message sent.  Event Type Code: 24; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 2.;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 19:00:14    Notice
DHCP Renew - lease parameters tftp file-^1/9A2FC592/res-600.0x30.0-D3.0 modified;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 14:12:28    Notice
DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 14:12:28    Error
DHCP Renew - lease parameters tftp file-^1/9A2FC592/res-600.0x30.0-D3.0 modified;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 02:59:22    Notice
DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/15/2026 02:59:22    Error
MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/14/2026 15:27:54    Warning
DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/14/2026 12:11:31    Error
DHCP Renew - lease parameters tftp file-^1/AC7C5946/res-600.0x30.0-D3.0 modified;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/14/2026 12:11:31    Notice
CM-STATUS message sent.  Event Type Code: 5; Chan ID: 30; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/14/2026 10:57:05    Notice
No Ranging Response received - T3 time-out;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/14/2026 01:30:01    Critical
DHCP Renew - lease parameters tftp file-^1/1CCD80F9/res-600.0x30.0-D3.0 modified;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/14/2026 00:36:42    Notice
DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/14/2026 00:36:42    Error
CM-STATUS message sent.  Event Type Code: 5; Chan ID: 30; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/13/2026 17:42:18    Notice
SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/13/2026 17:42:08    Critical
CM-STATUS message sent.  Event Type Code: 16; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 2.;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/13/2026 17:42:07    Notice
SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/13/2026 17:42:06    Critical
No Ranging Response received - T3 time-out;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/13/2026 17:42:03    Critical
SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/13/2026 17:42:02    Critical
CM-STATUS message sent.  Event Type Code: 16; Chan ID: 33; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 2.;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/13/2026 17:41:50    Notice
DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/13/2026 12:29:54    Error
DHCP Renew - lease parameters tftp file-^1/1CCD80F9/res-600.0x30.0-D3.0 modified;CM-MAC=(Edited private information);CMTS-MAC=00:01:5c:87:1a:54;CM-QOS=1.1;CM-VER=3.1;    02/13/2026 12:29:54    Notice

It looks like you’re referring to the event logs displayed on the gateway. To clarify, those event logs relate to your internet service connection rather than the gateway hardware itself. If any errors appear in the event logs, they can only be addressed and corrected by your Internet Service Provider (ISP).

We recommend checking the cable signal levels to ensure they are within the acceptable range.

Acceptable range is +15dBm down to -15dBm, if I read the specs correctly. The issues I have are with a signal level of +8dBm, on average. Upstream is at 42dBm, another 8dB pad will cause the upstream to be near or at the limit of 50 dBm.

But I get the jest of your replies. It’s up to me to figure out why my new cable modem is failing.

As mentioned earlier before, if you notice that these signal levels are outside the recommended range, we suggest contacting your ISP to have them reviewed and adjusted accordingly.

Because when the signal levels are out of the acceptable range, they can lead to the kind of connectivity issues you're experiencing.

What part of “My modem reports signals are all within specified range, but isn’t work properly.” is hard to understand?

Could you please confirm your subscribed internet speed plan?

Customer: My modem is dropping out even when it has a good signal.

Business: It must be you.

Customer: Modem reports everything is okay but not communicating with ISP.

Business: What is your ISP plan?

Customer: Within the specs of the modem. Modem is even recommended by ISP.

Business: It must be you.

Customer: You are right, it was me, and I solved the issue.

Business: How happy are you with our support team?

Customer: Very happy. They convinced me to go out and buy a new non-Arris modem. I now own a Netgear and it has been working flawlessly.

This is obviously a problem with the cable modem, this should be quite obvious given the shear number of complaints. The manufacturer doesn’t seem to care either time for a class action or a massive public awareness campaign to make everyone aware this company doesn’t care and want your business.

Modem rated DOCSIS 3.1, so 5Gb/s downstream, 0.8Gb/s upstream per ODFM channel, and it has two sets. DOCSIS 3.0 is not as good, but still Arris says it is a great modem for 1Gb/s plans.

My plan is 600Mb/s downstream and only 30Mb/s upstream.  Not exactly a challenging proposition for a modem rated 1Gb/s … at least one would hope.  Oddest part in all this was the hint things were a mess when ZERO downstream bits on ANY channel made it intact. 100% of the bits had to be corrected (not all of them could be).

Seeing 0.0% unerrored, 99.9% corrected, 0.1% uncorrected in my logs should have been an eye opener.

As an add: cable company says the G34 is generally a good modem, and why they recommend it… but they have been getting more complaints of this sort of thing.