Spectator

Modem constantly losing Internet

I have a Netgear CM500 modem and used to have rock-solid 100 mbit Internet. A while ago, I called and upgraded to a 400 mbit connection. There was no hardware change in the house and, from what I understand, outside the house.

 

Ever since then, my modem will disconnect from the internet and will stay disconnected. What fixes it is disconnecting the coax cable from it and connecting it again (power reset doesn't seem to do anything). Lately it has been happening twice a day at least and it is driving me crazy.


Can this be fixed? Is it on my side or the Spectrum's side?

 

Here is what my modem is saying:

 

TWC.PNGTWC2.PNGTWC3.PNG

9 REPLIES
Proven Sharer

Re: Modem constantly losing Internet

How long was your modem "up" when you took this data?  Leave it up for at least 6 hours before taking snapshots of the internal diagnostic pages.

Spectator

Re: Modem constantly losing Internet

The previous disconnection had happened around 4pm, so the modem had been up for at least 8 hours.

 

Today, it only went down once at around 11 am and seems to have fixed itself automatically. Modem uptime has been over 24 hours by now.

 

Any ideas?

Helper

Re: Modem constantly losing Internet

The upstream power levels are quite high. Is there a splitter connected before the modem that you can remove?

Spectator

Re: Modem constantly losing Internet

Thanks. There was. I removed it yesterday after the latest disconnect. Interestingly, I've also found that these disconnections are happening roughly at the same times of the day.

 

I'm just curious as this splitter had been there forever without issues and only now it is causing problems. Curious to understand what changed other than the hired bandwidth.

 

After removing the splitter, I did notice that upstream levels had been reduced and hopefully that will solve the problem, but we'll see what happens later today when the magical hour comes by.

Helper

Re: Modem constantly losing Internet

Upstream should now be in the 47 ish range, right?  Still a bit high but not on the edge like 51 is.  Let us know how it turns out. 

Spectator

Re: Modem constantly losing Internet

It is.

 

I'm at work now, but I have not gotten notifications from Google Wifi saying that my internet is down, which is a good sign.

 

Still curious to know what changed since it worked well before.

 

Would an increase in bandwidth from 100 mbits to 400 mbits cause something like this?

Helper

Re: Modem constantly losing Internet

An increase in bandwidth wouldn't necessarily cause the problem, but would make already existing problems more readily noticable.

Proven Sharer

Re: Modem constantly losing Internet

Uh-oh, the fine print shows bad news!! The speed change is the reason for your connection issue:

Spectrum has tested the Netgear CM500 and approved it for 300 MBps service, but NOT for a 400 Mbps connection.  Tell Spectrum to reset your account back to 300 Mbps, then ask them why they have been charging you for 400 Mbps when, according to their own published device certification listings, your customer-owned modem will not operate at 400 on the Spectrum network. 

The Netgear CM600 IS approved for 400 Mbps!

Spectator

Re: Modem constantly losing Internet

Interesting, because I typically have speeds that exceed 400 mbits. When it works, it is stable.

 

Good news is still no downtime since I removed the splitter.