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Motorola MB8600

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Motorola MB8600

I currently have the Arris SB8200  on the gigabit plan and im having a few issues with it.  First off if I loose power (Which happens somewhat often) for more than 10 seconds I have to have comcast reprovision the modem to get my speeds to go back to normal which is a pain.  The modem runs super hot and at times I notice inconstant speeds. I try to reset the modem through the xfinity app and by unplugging but I can only get speeds back to normal after comcast reprovisions the modem. After 6 days the correctables on the 3.1 upload channel can be in the billions-trillions and my signal strength is constantly fluxating so im wondering if I have a bad modem,

 

I was looking at the MB8600 and have a few questions.

1.  The MB8600 shows that it supports AQM.  I cant find any mention of the SB8200 supporting AQM

2. AQM appears to be part of the docsis 3.1 spec but doesnt necessarily have to be implimented.  Does comcase have AQM live.  several threads mentioned that comcast has it disabled.  

3.  According to some reviews the MB8600 handles poor signals better.  Is this true?

 

Im trying to determine if its worth switching to the MB8600 to see if its more stable but I dont want to do that if its going to just be a waste of money or should I look at getting a different SB8200.  If its true that the MB8600 supports AQM and the SB8200 does not and comcast has it live in the 3.1 network then I think it would be worth switching over and giving it a shot.  Anyone have any thoughts?


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Contributor

Re: Motorola MB8600

2 techs came out and replaced all the cables outside.  Removed one splitter and ran coax cables 2 the house.  One residental for family use and one buisness for my wife.  

 

Speeds range from 860 to 930 down.  Upstream signal is back to normal but downstream is still a little high.  They initally said they were going to monitor the signals for the next few days because they did notice a lot of fluxuation in the signal strength but before they left they were unsure if they were going to continue to monitor the signals or not.  

 

They do have to come back in a few weeks to bury the new cables.  At least I know everything is ok on my end and if the problem continues to occur then its a plant issue (the 2 techs did say there is a lot of continued maintanance going on in the area.  

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Contributor

Re: Motorola MB8600

Today my SB8200 has only been online for about 14 hours and I have about 160 Billion (yes Billion) corrected code words on the 3.1 channel. The 3.0 channels are all fine and show either 0 or under 50 corrected code words.

Is this normal. Comcast has been out and said my line and signal is perfect. The power of the channels range from +9 dBm to +14 dBm so a little hot but within spec and the modem is always crazy hot. I really think my modem may be bad which is why I’m looking at the MB8600
Expert

Re: Motorola MB8600


@JoeInPa wrote:

 

1.  The MB8600 shows that it supports AQM.  I cant find any mention of the SB8200 supporting AQM

 

2. AQM appears to be part of the docsis 3.1 spec but doesnt necessarily have to be implimented.  Does comcase have AQM live.  several threads mentioned that comcast has it disabled.  

 

If its true that the MB8600 supports AQM and the SB8200 does not and comcast has it live in the 3.1 network then I think it would be worth switching over and giving it a shot.  Anyone have any thoughts?


FWIW, see this post at the DSLR help boards about AQM;

 

https://www.dslreports.com/forum/r31883339-

 

"Said by jlivingood:
While AQM is in the D3.1 specs it is not yet implemented. When it's ready from the D3.1 vendors we'll start a trial to evaluate it. TBD timing on that (at least on the DS, which is implemented in the CMTS, whereas US is implemented in the CPE)."

 

"EDIT: My contacts at Comcast have confirmed that AQM has not yet been implemented in their network."

 

 

Expert

Re: Motorola MB8600


@JoeInPa wrote:

I currently have the Arris SB8200  on the gigabit plan and im having a few issues with it.  First off if I loose power (Which happens somewhat often) for more than 10 seconds I have to have comcast reprovision the modem to get my speeds to go back to normal which is a pain.

 

Perhaps consider an UPS?

 

 The modem runs super hot and at times I notice inconstant speeds. I try to reset the modem through the xfinity app and by unplugging but I can only get speeds back to normal after comcast reprovisions the modem.

 

Humm that's very odd. 

 

After 6 days the correctables on the 3.1 upload channel can be in the billions-trillions

 

It’s normal for the OFDM channel to have correctables and uncorrectables, it is not a cause for concern.

 

and my signal strength is constantly fluxating so im wondering if I have a bad modem,

 

I'd take a look at the signal issue before swapping modems. 

Start here: troubleshooting guide. Please post your equipment details (make/model of your modem/gateway/router) and a screenshot of your signal levels and your error/event log. Thank you!

 

 


 

Contributor

Re: Motorola MB8600

Thank you for the follow up.

Does that mean all docsis 3.1 modems will do AQM (once it’s live on the network) or does only certain modems have that technology.
Expert

Re: Motorola MB8600

Any make / model of DOCSIS 3.1 capable modem should be able to do it as it is part of the standard.

Contributor

Re: Motorola MB8600

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Contributor

Re: Motorola MB8600

I should also add that my wife has her own work modem as well so the line comes into the house.  Then goes into an inline power signal amplifier and then splits off to the main house modem and to her work modem.  The tech said the power amp was needed but the signals according to them are fine.  My signal will be +5 dBm one day then +14 dBm the next day

Expert

Re: Motorola MB8600

Your downstream signals are too high. I'd suggest removing the amp and checking your signal levels again. 

Contributor

Re: Motorola MB8600

I did attempt to do that and had issues reconnecting so the tech I talked to recommended I reinstall the in-line amp. I did reach out to arris and they did state the amount of correctables is alarming for such a short time. They also stated the fact that the modem needs re provisioned every time it’s restarted or power cycled is a problem.

I think I’m going to go down the road of getting it replaced because I really don’t like having to reboot/re provision of every week or so.

Now I just have to decide between the CM1000 and SB8600. I like the idea that the SB8600 does multi port aggregation that Comcast may support in the future.
Regular Contributor

Re: Motorola MB8600

Can we get an update on this, please? Thanks!

Contributor

Re: Motorola MB8600

I still have the same problems on and off. My modem has been online for about 2 days now due to a power outage and speeds seem to be good but the modem still runs very hot and I have tons of correctables on the 3.1 channel and the power levels have seem to have gotten higher (see attached image). 

 

I did attempt to remove the inline amp in the past and had no luck.  Also I noticed in the xfinity app I was getting a lot of “scheduled maintenance alerts” so I’m wondering if they did something to boost power from my node to the house. 

 

If if I try to remove the in line amp again does Comcast have to reprovision the modem again. I did removed the amp a few weeks ago it but speeds were stuck under 100 Mbps so I put the amp back in and everything went back to normal but I never called xfinity and asked them to reprovision the modem.  Im wondering if I need to take the amp out and have xfinity reprovision the modem for it to work properly. I’m afraid to take the amp out cause it’s working now. 

 

Speed test on the signals attached are ping 8, DL 910, UL 41.7. 

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Expert

Re: Motorola MB8600

Correctables on the OFDM channel are normal. And your signal levels are still way too high. 

Expert

Re: Motorola MB8600


@JoeInPa wrote:

 

If if I try to remove the in line amp again does Comcast have to reprovision the modem again. . 


No. Signals and provisioning are unrelated.

Contributor

Re: Motorola MB8600

Ok. So what do I do about it? Without the amp I can’t get any speeds over like 100 Mbps.

So do I just leave the amp in place even though the signals are so high? Does someone need to look at the signals coming from my neighborhood node?
Expert

Re: Motorola MB8600

@JoeInPa,

Bypass the amp for now - even if you get lousy speeds. That just eliminates "power levels are too high" as an issue. Can you post your levels w/o the amp, please? 

 

I've asked an employee to check the CMTS for real-time and historical RF signal reports from your modem. They can also check your local node/plant for any degradation or error reports. You can expect a reply in this thread. 

Contributor

Re: Motorola MB8600

Thank you very much for the follow up.  I did remove the in line amp and the speeds are normal (920 down 41 up).  The power levels still seem high.  

 

The one odd thing is now I have correctables and uncorrectables on both the 3.1 and 3.0 channels.  Before it looks like only the 3.1 channel was carrying the majority of the data now it looks like a lot of activity on the 3.0 channels too.  The screenshot is after my modem has been up for about 15 minutes and 3 speed tests.  And not to beat a dead horse but that still seems like a lot of correctables and uncorrectables for just 15 minutes of up time.  

 

Part of me wants to try the XB-6 modem (Technicolor version only) but im already paying 130 for the internet and tv. I dont really wanna pay another 11 bucks a month of it wont be any better. 

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Official Employee

Re: Motorola MB8600

Hello JoeInPa. I can assist with polling the CMTS for real-time and historical RF signal reports from your modem. I can also check your local Node/Plant for any degradation or error reports. Please send me a private message and include your full name and account primary phone number so I can access your equipment.

Contributor

Re: Motorola MB8600

Thank you.  PM sent

Contributor

Re: Motorola MB8600

Im hoping a tech visit helps.  I keep getting a lot of alerts in the xfinity app about scheduled maintenance being done in my area soon so im wondering if that has a lot to do with it.  

 

Official Employee

Re: Motorola MB8600

 I checked the diagnostics again this morning, and your signal is still severely degraded. A technician visit is certainly need to fix your speed issues. I have responded via PM. 

Contributor

Re: Motorola MB8600

I’m also wondering if the outside splitter is going bad. It looks pretty corroded.

I thought about swapping it out myself but I’m worried about how well the terminals would be sealed and I’m assuming it would probably be best to just have new ends put on the cable with the new splitter.

Lastly I’m wondering if I should have a second line ran to the house. Currently we have one line that runs to the house and hits a splitter outside. One line I Goes to my living room for the house personal service which has another splitter that goes to the modem and one to the TV. The second line of the outside line goes to my bedroom that runs my wife’s business modem for her work (yes I know this sounds dumb but her employer requires her work computer to be on its own wired business plan modem). So I wonder if that should have been on its own coax line.
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Official Employee

Re: Motorola MB8600

Most residential locations are only able to have a single cable drop line to the home. You can ask the technician about this when they get there. The technician should also evaluate the splitter and cable ends as part of troubleshooting. 

Contributor

Re: Motorola MB8600

2 techs came out and replaced all the cables outside.  Removed one splitter and ran coax cables 2 the house.  One residental for family use and one buisness for my wife.  

 

Speeds range from 860 to 930 down.  Upstream signal is back to normal but downstream is still a little high.  They initally said they were going to monitor the signals for the next few days because they did notice a lot of fluxuation in the signal strength but before they left they were unsure if they were going to continue to monitor the signals or not.  

 

They do have to come back in a few weeks to bury the new cables.  At least I know everything is ok on my end and if the problem continues to occur then its a plant issue (the 2 techs did say there is a lot of continued maintanance going on in the area.  

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Expert

Re: Motorola MB8600

Sweet! Look at those terrific signal levels. In spec and nice and clean.  

Contributor

Re: Motorola MB8600

I dont know if im being too picky or not but I noticed my downstream channels are starting to come back uo to between 9-12 like they were before. Upstream hasnt got higher than 48.5 that I noticed.  I also noticed that once every 3 minutes or so my tv picture gets pixilated/blurry for a second or so then goes back to normal.  My xfinity app still says there is pending maintenance in my area.  Im thinking now that the tech that came was right and he beleives this is likely a plant issue,  My speeds are still normal for now.  

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Contributor

Re: Motorola MB8600

Right after I sent that last message speeds dropped right back down to 30.  I did enter a chat with xfinity for them to refresh the modem and the speeds went back to normal.  It has to be either the plant still sending the fluxuating signals or my modem is bad.  Im wondering if switching out the MB8200 and getting an SB8600 will help.  Im wondering with the signals being so high and the modem running so hot if something on the inside got fried.  

 

It seems like I only have issues in the evening.  During the day my signal strength seems lower and I dont have speed issues, but at night my signals go up and the troubles start. 

Expert

Re: Motorola MB8600

Oh no! Smiley Sad

 

I'd shoot @ComcastJoeTru a PM and let him know what's happening. 

Official Employee

Re: Motorola MB8600

@JoeInPa. This is terrible news. Unfortunately, again this morning your Upstream Rx Power and D31 Down Rx Power are both out of spec. I received your PM and responded with our next steps. Thanks for your patience, while we continue to work toward resolving this for you. 

 

Contributor

Re: Motorola MB8600

It happened again twice today and both times I had to contact support to get the speeds fixed.  Im hoping to have my arris warrenty replacement modem by monday for my next tech visit but im pretty confident that the modem is not the issue but since its under warranty I may as well replace it just incase.  Everything seems to be pointing to an inconstant signal coming from the node and all wiring between the node and the modem is new.  Speeds are fine when the DL signal is around 5-6 and then speeds drop when the signal climbs to 9-10.  Then it drops back to 5-6 and everything will be normal.  

 

Lastly I did notice a new (what im guessing is a Filter) attached to the 2 way splitter.  Does anyone know what it is. the only writing i can find on it is "CS6-860   PPC 476"  

 

 

 

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Expert

Re: Motorola MB8600

That is a "cable simulator" manufactured by PPC. It's used for signal correction (excessive positive tilt).

Contributor

Re: Motorola MB8600

Thank you.  I did a bunch of web searching and couldn’t figure it out until I discovered PPC was the manufacturer. 

Contributor

Re: Motorola MB8600

Just wanted to give everyone an update. I got a automated voicemail from a stating the network technician found an issue in my area that has been repaired. My speeds and connection seem to be much more stable but it’s not perfect yet. My signals strengths are around 1-3 during the day and still climb to around 5-9 in the evenings. Upload signal stays from 46-48. But I still think it’s odd that my signal seems to go up that much at night. I did notice that my speed tests now top off at 880 pretty constantly vs the 930 I was getting before.

I did notice the “jitter” in my Speedtest start to go up and my average latency went from 5 to around 15ms (which I know is still very good).

Unfortunately my arris warrant replacement modem won’t be in for my scheduled tech visit on Monday so I had to change my appt to Wednesday. I wanted to have that in place for when they came out to do a final inspection after having new lines buried. I’m also wondering if now the “cable simulator” that was installed on the lines isn’t necessary anymore after the network tech fixed the issue which may be causing the jitter and increased ping so I wanted to have the tech check the lines signal again.
Contributor

Re: Motorola MB8600

I got my new modem and and after a lot of issues getting it activated it seems somewhat better.  For some reason the Comcast "Xfinity chat representative" who decided to stop responding to me mid chat said my modem still shows as offline. I did get it to work on my own but it still does show as off-line thought the Xfinity app.  

 

Signals seem the same with the new modem.  Power levels are back to climbing up to between 6-9.  They were between 1-3 for a few days after a network technician found an issue but as stated they are back to climbing up.  Without the cable simulator installed my signals are between 11-14 so they are still high.  The tech is still coming out Wednesday but i'm not sure what they can even do because everything between the neighborhood node and the modem have all been replaced and is brand new.  

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Contributor

Re: Motorola MB8600

Just another follow up.

Tech came out today and checked the new modem and lines all the way out to the “node” that feeds 4-5 other houses and she said everything looked fine. Signal strength on her meter said it was perfect. My modem was showing +2 to +3 signal strengths. Speeds were normal when she started but after unplugging the coax lines we power cycled the modem and the speeds dropped to 80. Had to send a refresh signal to get the speeds back to normal.

As of now the modem seems stable but the signal has climbed back up to +8 to +9. The tech blames the fluctuation in signal strength on the weather and doesn’t see any other reason why the signal would fluctuate that much. Also I should add that sometimes my modem (this is my new warranty replacement modem I got 2 days ago) shows as offline to xfiniity when it is clearly online.

The signals do seem pretty consistent as being normal during day and high at night. I’m not sure what else can be done other than continue to wait and see what happens and send a refresh signal when the speed drops. The tech did think that an XB6 modem may be more stable and can “auto correct” itself better when the signal fluctuates out of range but I’m already paying 30 bucks more for the gigabit service I don’t wanna pay an extra 11 when my modem is more than capable of the speeds.
Contributor

Re: Motorola MB8600

Well my speeds dropped again. I came home from work and my DL speeds were down in the 80’s and the downstream powers were back up between +8 to +10. I was not able to reset the modem through the xfinity app (it was saying it can’t connect to the modem) so I had to manually power cycle it. Speeds came back to normal but it’s getting frustrating resetting the modem. I went ahead and had a forum rep order me an XB6-T modem hoping that would help. I’m still waiting on confirmation on when I will get it.

Hopefully XB6-T helps cause I’m getting tired of resetting the modem. I would rather use my own modem but of it means having better service and getting to use the phone I’m already paying for I may as well give it a shot.
Contributor

Re: Motorola MB8600

Also my xfinity 4K HR box is “stuttering” when I watch any content through the box. It comes and goes and just started doing that today. The best way I can describe it is that the tv picture looks like a bunch of fast still pictures. It’s really weird and I have never seen the TV do that before.
Official Employee

Re: Motorola MB8600

Hello, I can assist you further from here. To protect the privacy of your account, please send me a private message verifying your full name, street address including city, state, and zip code (and apartment number if one is associated), and the full account number or phone number associated with your services. To send a private message click on my name, then click private message me.