Modem Self Restarting. What is the cause?

[TripleBullet]

So I had an Ubee D3.0 modem rented from Comcast and it would restart by itself randomly. Not fun. Usually once a day. So I went and got a Motorola Surfboard SB6121. Cool, problem solved. Plot twist. Nope. This one restarted the exact same way as the last. So I can almost confirm the modems aren't at fault.

So I swap out all the cables (Besides one from wall). Just to make sure it isn't bad cables. Good for a day or so. Restarts again. Continues to do so to this day. The restart is also a full reboot. Almost as if Comcast keeps sending my house a refresh signal.

I called them. They have no records of anything as far as them causing the restart. Everything checks out on their end. You know the usual bs. Only thing Comcast could do is send a tech out. Which I would love to avoid because yk. It's Comcast. I also have a splitter for the cable in my room. So one is to the TV box and other to modem. Also, the cable box never has issues as far as signal drops or anything. Which to me may say the splitter could be ok. Regardless, the splitter will get swapped. I was thinking that is probably next best bet but wanted to get some lovely insight on Tom's.

So what do you think could be some possible issues?

 

[daswilhelm]

get rid of the splitter, run a direct coax line to the modem and use it for a few days, see how that reacts.

 

[TripleBullet]

get rid of the splitter, run a direct coax line to the modem and use it for a few days, see how that reacts.

That is a good idea but I'm going to get a new splitter tomorrow. I work at Best Buy so they are super cheap with discount. I think I might try it anyways though. I'll start it tmmrw since no shows are on.

 

[daswilhelm]

i wouldnt trust best buy splitters.

in fact, i don't recommend splitters at all.

you optimally want a "home run" or a line direct from the pole to your modem, any tvs should be ran off of a seperate line.

 

[Shaun o]

Yep Depending on the modem, if the line attenuation is low or fluctuates.

And the channel locks are lost, based on how many are locked on your subscriber broad band speed.
The modem it`s self will force a restart. Due to channels tuning straying. because of low voltage or very high Db noise on the cable line.

Based on how low the voltage level is for each locked channel, and each of the channels that are locked how high or low the DBvm values are.

If you find the ratings are low in Mv readings withing the cable modems diagnostic table settings of the modems firmware.

Your splitter is faulty. Or on the line that connects to your cable modem it is running already off a line with a splitter on it.
If the case do not add another splitter, remove one instead from the cable line to gain a better voltage feed for channel lock and to get a stronger cleaner Db signal ratio.

 

[TripleBullet]

Yep Depending on the modem, if the line attenuation is low or fluctuates.

And the channel locks are lost, based on how many are locked on your subscriber broad band speed.
The modem it`s self will force a restart. Due to channels tuning straying. because of low voltage or very high Db noise on the cable line.

Based on how low the voltage level is for each locked channel, and each of the channels that are locked how high or low the DBvm values are.

If you find the ratings are low in Mv readings withing the cable modems diagnostic table settings of the modems firmware.

Your splitter is faulty. Or on the line that connects to your cable modem it is running already off a line with a splitter on it.
If the case do not add another splitter, remove one instead from the cable line to gain a better voltage feed for channel lock and to get a stronger cleaner Db signal ratio.

Ok, that makes sense. Any idea as to why this didn't happen before a few months ago? I have been at this house for about 4 years and only just the past year it seems to have began. Not sure if this info helps or not. I will grab a splitter tomorrow and see if anything changes. If not I will direct link.

 

[TripleBullet]

i wouldnt trust best buy splitters.

in fact, i don't recommend splitters at all.

you optimally want a "home run" or a line direct from the pole to your modem, any tvs should be ran off of a seperate line.

We have name brand splitters. Definitely not grabbing an Insignia lol. I'm pretty much stuck with a splitter unless I don't want cable tv unfortunately.

 

[daswilhelm]

i wouldnt trust best buy splitters.

in fact, i don't recommend splitters at all.

you optimally want a "home run" or a line direct from the pole to your modem, any tvs should be ran off of a seperate line.

We have name brand splitters. Definitely not grabbing an Insignia lol. I'm pretty much stuck with a splitter unless I don't want cable tv unfortunately.

Brand Name doesn't mean its going to work with a cable modem, splitters are designed for tv's. you can use, at most, one splitter between your incoming line and your modem, any more than that, or using the wrong splitter, will affect your performance.

 

[daswilhelm]

Yep Depending on the modem, if the line attenuation is low or fluctuates.

And the channel locks are lost, based on how many are locked on your subscriber broad band speed.
The modem it`s self will force a restart. Due to channels tuning straying. because of low voltage or very high Db noise on the cable line.

Based on how low the voltage level is for each locked channel, and each of the channels that are locked how high or low the DBvm values are.

If you find the ratings are low in Mv readings withing the cable modems diagnostic table settings of the modems firmware.

Your splitter is faulty. Or on the line that connects to your cable modem it is running already off a line with a splitter on it.
If the case do not add another splitter, remove one instead from the cable line to gain a better voltage feed for channel lock and to get a stronger cleaner Db signal ratio.

Ok, that makes sense. Any idea as to why this didn't happen before a few months ago? I have been at this house for about 4 years and only just the past year it seems to have began. Not sure if this info helps or not. I will grab a splitter tomorrow and see if anything changes. If not I will direct link.

it worked four months ago because your signal quality was better. things that change? your incoming signal, a splitter going bad, a coax cable going bad, a squirrel chewing through your wires, etc etc etc.

 

[TripleBullet]

Yep Depending on the modem, if the line attenuation is low or fluctuates.

And the channel locks are lost, based on how many are locked on your subscriber broad band speed.
The modem it`s self will force a restart. Due to channels tuning straying. because of low voltage or very high Db noise on the cable line.

Based on how low the voltage level is for each locked channel, and each of the channels that are locked how high or low the DBvm values are.

If you find the ratings are low in Mv readings withing the cable modems diagnostic table settings of the modems firmware.

Your splitter is faulty. Or on the line that connects to your cable modem it is running already off a line with a splitter on it.
If the case do not add another splitter, remove one instead from the cable line to gain a better voltage feed for channel lock and to get a stronger cleaner Db signal ratio.

Ok, that makes sense. Any idea as to why this didn't happen before a few months ago? I have been at this house for about 4 years and only just the past year it seems to have began. Not sure if this info helps or not. I will grab a splitter tomorrow and see if anything changes. If not I will direct link.

it worked four months ago because your signal quality was better. things that change? your incoming signal, a splitter going bad, a coax cable going bad, a squirrel chewing through your wires, etc etc etc.

Well I just got the new splitter and hopefully if I get super lucky it will stop. If not I will run direct to modem and see where it goes after that.

 

[daswilhelm]

very good, best of luck.

 

[TripleBullet]

Update - I've switched the splitter. No restarts yet. Keyword "yet". Also, only been a few days. Here is the splitter I swapped it with.

http://www.bestbuy.com/site/rocketfish-2-way-coaxial-splitter-gold/6651202.p?id=1218768949178&skuId=6651202

Not sure if this a good splitter or not but it's what we had at work.

 

[daswilhelm]

whether its good or not doesn't really matter when its working, so if its going well for you so far, keep using it.

just keep in mind they don't last forever. they are very susceptible to damage from lightning strikes and power surges on the coax line, so if it last 4 months and starts causing problems again, just replace them. not sure about your provider, but the ISP i used to do help desk for would provide them for free.

 

[daswilhelm]

and if you really want to see if its quality or not, crack one open and see whats inside. if theres just a wire split in two, its junk. the better units have a pc board that separates signals correctly.

 

[TripleBullet]

whether its good or not doesn't really matter when its working, so if its going well for you so far, keep using it.

just keep in mind they don't last forever. they are very susceptible to damage from lightning strikes and power surges on the coax line, so if it last 4 months and starts causing problems again, just replace them. not sure about your provider, but the ISP i used to do help desk for would provide them for free.

I have Comcast. I'm sure they would but I can just get them from work for like 2 bucks. Good to hear though. Hopefully it's fixed and not just waiting to DC when I am playing some kind of ranked game lol.

 

[daswilhelm]

i hear ya, bad internet is no fun.

 

[TripleBullet]

and if you really want to see if its quality or not, crack one open and see whats inside. if theres just a wire split in two, its junk. the better units have a pc board that separates signals correctly.

Noted, if this doesn't fix the issue i will.

 

[TripleBullet]

i hear ya, bad internet is no fun.

Ok, so Modem did restart with the splitter. As I expected. So I went direct line and skipped the splitter. It also restarted without a splitter. So I think im going to call Comcast and have a tech come out to test my line's strength. Does that sound like the next logical step or is there something else I can do?

 

[daswilhelm]

that's exactly the next step. If you ask nicely enough, they might just run you a new line just for your modem.

the only other thing you can do, is trace the coax cable, and see where it goes.

 

[TripleBullet]

that's exactly the next step. If you ask nicely enough, they might just run you a new line just for your modem.

the only other thing you can do, is trace the coax cable, and see where it goes.

Ok cool. My line comes from the attic. Total pain to get to but I just might try tomorrow. Probably will still be calling a tech. Hopefully squash this once and for all. I guess we will see.

 

[daswilhelm]

the tech is your best bet, but sometimes i would have customers trace the cable, and find a few other unnecessary splitters along the way.

 

[TripleBullet]

the tech is your best bet, but sometimes i would have customers trace the cable, and find a few other unnecessary splitters along the way.

Yeah, well the guy who did our stuff when we moved in was a contractor for Comcast and did a <Mod Edit> job. We called Comcast and they said we were the last complaint before he got let go. So I am sure he did something terrible up there. Well, more like lazy.

 

[daswilhelm]

the tech is your best bet, but sometimes i would have customers trace the cable, and find a few other unnecessary splitters along the way.

Yeah, well the guy who did our stuff when we moved in was a contractor for Comcast and did a shit job. We called Comcast and they said we were the last complaint before he got let go. So I am sure he did something terrible up there. Well, more like lazy.

haha that sounds typical. maybe you will have better luck with the next tech.

 

[TripleBullet]

the tech is your best bet, but sometimes i would have customers trace the cable, and find a few other unnecessary splitters along the way.

Yeah, well the guy who did our stuff when we moved in was a contractor for Comcast and did a shit job. We called Comcast and they said we were the last complaint before he got let go. So I am sure he did something terrible up there. Well, more like lazy.

haha that sounds typical. maybe you will have better luck with the next tech.

He won't be a contractor put it that way lol.