S33 | S34

I had a problem with cable system which Xfinity fixed by running a new line.  Once activated, my modem connected to the internet but I’m unable to sign in to the modem.  I reset to factory default but it will not accept the default user id and password which came with modem (Admin / password).  I need to access in order to reset my home network.  I’ve tried unsuccessfully to contact anyone with Arris support for assistance or warranty.  I need the modem for work ASAP so will be forced to purchase a new modem (which wiill not be this company brand) unless I can get help immediately.

Got Xfinity to activate and working but can’t log in to admin portal

Just hooked up my S33 and had it activated through Xfinity. I connect to my WiFi router and works great. However,  when I unplug from router and hook my modem directly to my laptop, it says unidentified network and it will not connect to the internet. Any suggestions?

Both Arris and Xfinity pointing fingers at each other.  Paying for 1.2 gig and getting between 200 and 400 on ethernet.  Was getting 900plus on xfinity modem.  Attached are logs if someone can help me.(edit: CM-MAC information removed)31/12/1969 17:02:19 3 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=**:**:**:**:**:**;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1; 31/12/1969 17:02:22 3 No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=***.***.***.***;CM-QOS=1.1;CM-VER=3.1; 18/3/2023 07:09:40 3 SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=***.***.***.***;CM-QOS=1.1;CM-VER=3.1; 18/3/2023 07:09:49 3 No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMT

My T-Mobile Cell Spot (a mini home tower so I get strong signal throughout my home) worked for 2 years without problems. We had to change the primary person name on account and they made us return cell spot and get a new one because according to the FTC it has to be registered in that exact person’s name. Waited to install new cell spot until Arris S33 and EERO mesh pro were installed so it was all new. Everything was working for 7 days and then cell spot went out. Made several attempt to reboot and talk to T-mobile tier 2 tech support. They say that I need to open the following 3 ports so T-mobile cell spot can connect to the internet:UDP 500UDP 4500UDP 123Everything else works great but my cell spot and I fluctuate from 1-2 signal bars. I need it to be back at full 4 throughout my home. It isn’t spectrum nor EERO and T-mobile is saying it is the modem. Unfortunately, I can’t find anywhere that has the ability to change any port settings 

Please forgive my ignorance of networking for this question.  I plan to connect the S33 to my EdgeRouter-4 and will use Xfinity as the ISP.  When I first attempted this (which I am certain I did not do correctly), the modem had an IPv6 address assigned to it.  My EdgeRouter-4 is currently setup to only work with IPv4.  If I activate the modem (correctly, this time) is it capable of receiving an IPv4 address from Xfinity, or do I need to adjust something in my router setup to accommodate an IPv6 address from Xfinity? Thanks.

I have the S33 and Archer Gx90 router, when I type the default IP. 192.168.100.1.  It times out so I cannot log into the modem to check status... If I unhook the router its works fine..... I just dont want the annoying process.    Thanks

I purchased the S33, how can I tell if it's the v2 model?

I’m trying to connect Google Mesh Pro to my S33 for wireless internet.  I previously had this working for years.  I just switched to Xfinity Residential and I cannot get the Google Mesh to connect with the Arris.  It says ‘No Internet Connection’.  Wired connection is working fine.  The MAC address of the modem is registered with Xfinity. I found a post on Google Nest site that someone else had the exact same problem.  They registered MAC and SSN with Xfinity, but the post said they ‘got with Arris’.  It sounds like Arris had to do something?  Here is the part of the post “ I reached back out to Xfinity, gave them the information (they all of a sudden knew the issue once I had the answer) and then that’s where your suggestion came in. They sent me along to Arris and they then somehow connected my Nest Pro to the Modem. “

I just got the S33 as my previous modem was no longer supported and I had been having connection issues.  With the S33 I am still having connection issues, I believe it’s the line, but in trying to troubleshoot myself I went to look at the Event Log and nothing shows up.  Why is this?  Do need a new software version?  All my status parameters are fine.

My Arris Surfboard S33 will not connect to the internet after the Cox truck was outside yesterday. Cox claims there is no connectivity issue, but router is just stuck with a solid blue light now and none of our devices can connect. Any thoughts?

I have a brand new s33 that constantly disconnects every few minutes briefly. I have cox communications for an isp. I contacted their tech support and they checked by sending a signal and restarting the modem. They said everything looks fine on their end and that it must be the modem. I’ve tried multiple routers with the same problem. It started 2 days ago out of nowhere. Does anyone know what could be the problem 

I have a brand new s33 that constantly disconnects every few minutes briefly. I have cox communications for an isp. I contacted their tech support and they checked by sending a signal and restarting the modem. They said everything looks fine on their end and that it must be the modem. I’ve tried multiple routers with the same problem. It started 2 days ago out of nowhere. Does anyone know what could be the problem 

I have a brand new s33 the internet constantly disconnects every few minutes very briefly. I have cox communications cable internet. After speaking with their tech support they said they sent a signal to the modem and restarted it but the problem persists and they stated everything seems fine from their end. I have tried multiple routers with the same persisting problem. Does anyone know what could be the problem thanks 

I have a s33 modem and need to change the date format from dd/mm/yy to the yy/mm/dd as the old motorola 6120 modems did in there event log.   also why is there not a option to send to a syslog server. it seems we are going backwards in usability. And before you give the standard line, even a raspberry pi can do this. 

This has happened a few times now, but this time it has not come back on after 12 hours.  Router indicating no internet, and attempts at using wired ethernet connection have failed. Oddly enough the light remains blue even when I disconnect the coaxial cable.  The unit is only about a year old.  Any ideas?

I’ve got the infamous 1.2gig service from Xfinity, they have checked and replaced everything they have changed the channel that my box connects to to their service, my speeds have not exceeded 500 mbps which is less than half. I thought it was a double NAT issue because they can only provide their own gateway modems which act as routers as well, but it’s still happening with the new S33 Arris modem I purchased just last week. Is anyone else having this problem? Is there a quick fix to cause the modem to recognize at what speeds it should be getting?I have the app, but it’s no help for this problem whatsoever.

My S33 requests an option that Optimum DHCP doesn’t support.  So, the DHCP server responds with an error, which takes time to resolve;  During that period I lose internet connectivity - annoying in the middle of a movie.(edit: CM-MAC information removed)09:42:25 3 Successful LAN WebGUI login from ***.***.***.*** on 23/01/26 at 9:42 AM. 26/1/2023 23:20:52 4 DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1; 26/1/2023 23:45:06 3 Successful LAN WebGUI login from ***.***.***.*** on 23/01/26 at 11:45 PM. 26/1/2023 23:58:48 3

I have purchased a arris surfboard S33.  When I set it up the green light keeps flashing and my computer won’t work? 

Xfinity just upgraded me to 800 Mbps (in return for a $10/month fee increase!).  They also informed me, however, that my existing equipment would NOT support such an increase.  In response, I bought and installed an S33, plus a Linksys AC1200, using their 2.5 Gbps LAN ports.  Although the modem seems to be working well, the one fly in the ointment, so to speak, is that, although the LED flashes orange, and then green, when the modem powers up, instead of showing blue, the LED seems to go blank!  In spite of this, however, my internet speed has increased well above the 800 Mbps mark, ranging from 900 to about 912 Mbps, and seems to be working smoothly!  I do know that the area where I live is on the outer fringes of their network in this area.  Could that have something to do with the LED not showing blue?  In any event, how should I proceed?  Thanks in advance for any advice or assistance!

Last month, I switched ISPs to Xfinity with an 800Mbps plan, but continue to use the same s33.  I have noticed my download speed will occasionally drops to be around100Mbps, independent of whether I use the 1Gitabit or 2.5Gigabit port.  using my ORBI router statistics, I can see the WAN port drops to 100M/Full down from 1000M/Full.  To get my speed back, I have to reconnect my patch cable (CAT6) from the modem to the router to the opposite port on the modem (1 vs. 2.5Gigabit). Sometimes I have to reboot the modem as well.   Unfortunately, I don’t know exactly when this change happens so I can’t check the event logs at that specific moment. I have seen this with my previous ISP as well, so I don’t think this is specific to the ISP.  So what would cause this?  How can I resolve?While investigating this issue, I did look at the event log to see if I can find anything unusual.  Two things I have found, but may or may not be related.(edit: CM-MAC information removed)

Connecting S33 to either my RAX50 (Gbe) router or GS110MX 10G Switch fails, but it connects fine to my PC.  Any ideas why?  Using Cat 8

I find that my 1.2 Gb speed from Xfinity periodically slows down from about 900 Mbs to about 100 Mbs.  This is remedied by restarting the modem by unplugging it for about a minute.  Is there a way to schedule a periodic restart of the S33 modem via its app?   I am thinking that, if not, I could connect it to a smart plug and schedule it to periodically turn off and on in the middle of the night.Also how often should the modem be restarted for optimum performance?

Purchased S33 modem May 2022. Kept overheating and dropping network connection. Spent 2 hrs troubleshooting with Cox and said modem is bad. Requesting assistance with warranty replacement. Thanks. 

Simply put I have Xfinity 1.2 gig service with a not even year old S33 modem.  When I plug my Chromebook via gigabit Ethernet adapter into the 2.5 or 1 gig port I get around 500-600 mbps down.  Xfinity tech comes out & connects his meter to the incoming cable & showed me it was getting 1.299 gig.  Then he plugged his meter into the cable coming out of the 2.5 gig port and it also showed 1.299 gig down.  That’s the first issue, now the rest of it that makes no sense to me;I have a band new Amplfi Alien router w/ the LCD touch screen.  It shows Xfinity’s speed coming into the router usually between 750-810 mbps but when I plug my Chromebook into one of its LAN ports I get 570 mbps down which I don’t understand.  Then here’s the last piece that makes me even more perplexed;I have a TP-Link RE650 gigabit range extender (which is connected via wifi to the Alien router) and when I plug my Chromebook into the LAN port on the range extender I get speeds of 720-800 mbps