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386.7 Internet Dropping every few days/weeks

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Did you ever get this resolved?

Which ISP did you work with?

A bunch of us are having issues with the MB8611 Modem on Xfinity starting in December & more so frequently now (~1x per 30 mins in some instances).
But no one on either side is owning up to the issue even after the modem has been rock solid for so many.

Want to hear if you had some news on your issue which sounds exactly (logs & all) like current problems we are having.

Xfinity probably rolled out a firmware update for that modem. Hopefully they'll roll out a fixed one soon.

Never have been a fan of the MB series motorolas. The surfboard is the gold standard (now owned by Arris but so far they haven't f'd it up too bad). No idea why motorola would sell off the cream of the crop and keep the sub-par line.

I'd say check your signal levels but if it is a widespread issue then seems more like a firmware problem. You can find out the firmware version and go see when it was rolled out potentially.

Some modems will drop the ethernet when the coax drops, so you can check the logs and signal levels and see if it seems to be signal related. Maybe they're bonding more channels (they did recently up the speed so that seems likely) and a signal that was ok before may be bad now.

If your signal levels are bad look into splitters, if possible you want your modem off a single -3.5db port (2 way splitter or unbalanced 3 way with one -3.5 and two -7 ports). You can also use a two way that feeds the modem off one port and another splitter for other things off another port. If that doesn't help, have the drop to your house and/or internal coax replaced. If the guy is nice and has a spool, he might run RG11 for you, had that done here years ago and he left me the rest of the spool to run internally. Of course I no longer use cable but nice to have it there.
 
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Oh great... not what I wanted to hear. I just ordered (and was delivered today) a Motorola MB8611 modem today to take advantage of my 1.5Gb bandwidth and 2.5Gb port on the GT-AX6000. I was planning on activating it tomorrow morning, so I'll check in if I experience any weirdness.

Have you been able to log into the modem interface and look at its logs? That's what I had to do a few years ago when troubleshooting an Xfinity connection issue.
Hey @username0475 ... I decided to install my MB8611 yesterday evening... so I've been going about 22hrs with no ill effects or any WAN issues to report as of yet. I'm so glad to see the process is so easy now for us consumers to add our own equipment to the mix. Just a few years back, you still had to deal with techs and house visits to make this all happen.

Running speedtest through RTRMON is yielding me about 1440Mbps, so things seem to be working well...

As I mentioned, I had some trouble with Xfinity a few years back, and they kept blaming it on my own equipment, or the wiring in our house... I was able to use the logs I gathered from the modem itself to show that there was some serious connectivity issues, voltage, latency, etc. happening. I asked if there was anything else they could do from a troubleshooting aspect, and Xfinity support ended up putting some kind of a monitor on my line to watch the stats more closely, and ended up determining from that that the issue was upstream. Fixed next day, and have had a strong uninterrupted signal ever since.
Hey - just getting back to this.
Very frustrated that Moto & Comcast couldn't sort it out, so I had to buy another modem (Arris S33) since Comcast was not going to own up to anything & the 2 techs they sent out said my signal from the corner drop to my house was the last on the street - so pipe was all coming through to my house.

Finally, Moto offered to replace the modem & stated they were aware of the issue with the firmware causing frequent resets but so far no resolution with Comcast is forthcoming.

There are a lot of complaints on the official Xfinity forums: https://forums.xfinity.com/conversations/search?q=MB8611&sortKey=RECENT&page=1
And a few on the Reddit also.

There are some reports that that Moto & Comcast have rolled back to the prior version of the firmware ( Prior = 8611-19.2.20 is stable, "current" = 8611-21.3.7) in the above forum links. But I have not confirmed if it has stopped the drop outs totally yet.

the Arris S33 has worked great but again - it's still the honeymoon period & with Moto Modems being bulletproof most of my 30+ years using them, I find it hard to believe that Moto is the cause & Comcast played no part in this (latter with their network configurations & updates)
 
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Xfinity probably rolled out a firmware update for that modem. Hopefully they'll roll out a fixed one soon.

Never have been a fan of the MB series motorolas. The surfboard is the gold standard (now owned by Arris but so far they haven't f'd it up too bad). No idea why motorola would sell off the cream of the crop and keep the sub-par line.

I'd say check your signal levels but if it is a widespread issue then seems more like a firmware problem. You can find out the firmware version and go see when it was rolled out potentially.

Some modems will drop the ethernet when the coax drops, so you can check the logs and signal levels and see if it seems to be signal related. Maybe they're bonding more channels (they did recently up the speed so that seems likely) and a signal that was ok before may be bad now.

If your signal levels are bad look into splitters, if possible you want your modem off a single -3.5db port (2 way splitter or unbalanced 3 way with one -3.5 and two -7 ports). You can also use a two way that feeds the modem off one port and another splitter for other things off another port. If that doesn't help, have the drop to your house and/or internal coax replaced. If the guy is nice and has a spool, he might run RG11 for you, had that done here years ago and he left me the rest of the spool to run internally. Of course I no longer use cable but nice to have it there.
I had 2 techs from Comcast come out on diff occasions & all signal & lines were optimal to reference quality LOL.
So yes, line, connection & signal checks were part of both visits.

To me this was Moto rolling out a firmware based on Comcast specs & Comcast probably didn't do any QC on their 3rd party guidance prior to ensure compatibility.

Us customers were victims of this lack of coordination & communication between 2 corp entities.

And so I switched to a Arris S33 cause I was @ my wit's end being dropped every 30 mins while I was on business video calls.
So far, so good.

**ps** wish I wasn't so emoitonally involved else I would have done some cabling upgrades like you! LOL!
 
I'm using a RT-AX86U running 386.7. Every so often the internet will go down. I was able to catch it occurring last night and have that portion of the logs below.

Can anyone shed some light on what might be going on?
You should probably have your line checked. There may be a problem with your SNR margin or line weakening values.
 
Hey - just getting back to this.
Just wanted to check back in, and reporting 0 issues sofar on the MB8611 using Xfinity. Wondering if perhaps it was a local/regional issue in your neck of the woods, perhaps?
 
I had 2 techs from Comcast come out on diff occasions & all signal & lines were optimal to reference quality LOL.
So yes, line, connection & signal checks were part of both visits.

To me this was Moto rolling out a firmware based on Comcast specs & Comcast probably didn't do any QC on their 3rd party guidance prior to ensure compatibility.

Us customers were victims of this lack of coordination & communication between 2 corp entities.

And so I switched to a Arris S33 cause I was @ my wit's end being dropped every 30 mins while I was on business video calls.
So far, so good.

**ps** wish I wasn't so emoitonally involved else I would have done some cabling upgrades like you! LOL!

Well that's pretty much how android updates work too, roll it out and let the user base be beta testers.

I've had experience with two of the non-Surfboard Motorola gateways and both were afwul. Would much rather have a surfboard modem and a good router like Asus or even TP Link.

Did work with one of the SBG (surfboard modem/router) and it wasn't bad but the router/wifi function was nothing special, and did not like the fact that the ISP controls the router portion of the firmware and can even lock stuff out.
 

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