Participant

SYNC Timing Failures, Fail to Acquire FEC, Unusual Power Levels, Work VPN Dropouts

Internet Only Customer, 200/10; Summerville, SC

Modem: Zoom 5370, Software Ver 5370-5.5.10.1

Router: ASUS AC 1900, Firmware Ver 2.112 Updated 2/11/19

 

Had problems w/streaming TV and the wife's work VPN dropping in and out today. Checked modem logs and found never before seen power levels and errors in the log (posted below).  Rebooted modem and router without much change in stats and VPN still experiencing problems.

 

Background: About a month ago we had major connectivity and speed problems. Phone tech saw signal issues and rolled a truck. Tech ruled out any problems in home and called repair for line problems elsewhere. The next day problems disappeared and markedly improved signal stats. Also posting a screengrab representative of those stats for comparison.

 

Before Today

after repairs.png

 

Today

connectivity problems - 2019-02-25_125406.png

 

connectivity problems-event log- - 2019-02-25_125406.png

 

Just checked modem stats again

2019-02-25_174804.png

Current Speed Test

DSLReport-.png

 

So, what do the ~  -.8  to  -3 dBmV numbers mean?

 

Thanks, Ken

5 REPLIES 5
Participant

Re: SYNC Timing Failures, Fail to Acquire FEC, Unusual Power Levels, Work VPN Dropouts

VPN problems again this morning. Stats and log below. Note the DHCP error at 09:02, what does that mean?

2019-02-26_091922-event log.png2019-02-26_091704.png

Community Manager

Re: SYNC Timing Failures, Fail to Acquire FEC, Unusual Power Levels, Work VPN Dropouts

@KenH99 , 

 

Hi Ken!  The -.8 to -3 dBmv is the power level for your downstream bonded channels.  The acceptable range is  -15 dBmV to 15 dBmV, so you are well within the range.   

 

I was able to locate your account, based on your registration information,  and your signal levels all look good.  Two things do stand out, however.  What you describe sounds like an intermittent issue.  On your account, I am seeing a device attached to the modem (looks like a printer - says Hewlett Packard - but could be the router).  For a device to be attached to the modem, the modem will need to hand out IP addresses.  You also mentioned that you are using your own ASUS router.  Any devices, including the printer, should be getting IP addresses from the router, not the modem directly.  The modem should be in bridge mode and all addresses should be handed out by the ASUS router.  If the modem is handing out addresses, that is called "double-nat" and can cause intermittent conflicts, similar to what you describe.  If the printer is attached to the modem,  then connecting it to the router may also resolve the issue.  This could be causing the sync issues that you are seeing on the modem logs.  

        

The second issue is the that the Zoom 5370 is a minimally qualified modem.  What this means that it may work, and there may be times when it doesn't, because it does not meet all the specs to run on our network.  I included a link to Approved Modems.  It does not neccesarily mean that it needs to be replaced, but swapping it for another modem would help rule out if the modem is causing the issue.  

 

If the modem is in bridge mode (we are unable to access because it is your equipment), then I would suggest replacing the modem.  Either choose one that is capable up to 300Mbps on our network for your 200Mbps service, or you can get a free modem at a Spectrum store.  Since you have your own router already, you would just want the Spectrum modem in bridge mode.  You would still manage your network and wireless with the router.   

 

If you are reluctant to exchange the modem, you can also look for loose or corroded connections and splitters that are either malfunctioning or not terminated.  Last, ensure the VPN connection is over an ethernet connection.  Wireless VPN can be impacted by ingress from other signals, like cell phone signals.    

 

Hope this helps.  Let us know if you have other questions.   

 

For direct support, please contact us at: 

 

 

Participant

Re: SYNC Timing Failures, Fail to Acquire FEC, Unusual Power Levels, Work VPN Dropouts


@James_M wrote:

@KenH99 , 

 

Hi Ken!  The -.8 to -3 dBmv is the power level for your downstream bonded channels.  The acceptable range is  -15 dBmV to 15 dBmV, so you are well within the range.   

 

Why the sudden marked change in downstream signal levels? See my before and after connection stats above. 

 

I was able to locate your account, based on your registration information,  and your signal levels all look good.  Two things do stand out, however.  What you describe sounds like an intermittent issue.  On your account, I am seeing a device attached to the modem (looks like a printer - says Hewlett Packard - but could be the router).  For a device to be attached to the modem, the modem will need to hand out IP addresses.  You also mentioned that you are using your own ASUS router.  Any devices, including the printer, should be getting IP addresses from the router, not the modem directly.  The modem should be in bridge mode and all addresses should be handed out by the ASUS router.  If the modem is handing out addresses, that is called "double-nat" and can cause intermittent conflicts, similar to what you describe.  If the printer is attached to the modem,  then connecting it to the router may also resolve the issue.  This could be causing the sync issues that you are seeing on the modem logs.  

 

1.  Nothing is connected to the modem but the ASUS router. Our HP printer is in another room (home office) connected to a PC and shared across the network via that PC, besides it stays off most of the time. There is another router configured as a bridge, connected via ethernet to the primary ASUS router. The bridged router only provides WiFi and no devices are connected to it.  Home office  devices are on a network switch that is fed by ethernet from the ASUS router. 

 

2. I'm unfamiliar with modem bridge mode nor how to confirm it's in that mode.  Can you point me to instructions to determine the modem's mode? However, IF it was NOT in bridege mode the problems you described would certainly have occured before now.  The modem has been in operation for ~2 years w/o any issues and providing good stats as shown in the 'before' stats page I posted.

        

The second issue is the that the Zoom 5370 is a minimally qualified modem.  What this means that it may work, and there may be times when it doesn't, because it does not meet all the specs to run on our network.  I included a link to Approved Modems.  It does not neccesarily mean that it needs to be replaced, but swapping it for another modem would help rule out if the modem is causing the issue.  

 

It wasn't minimally qualified when I bought it but we'll get a Spectrum modem later this afternoon. Does Spectrum disable customer access to connection stats and logs on their issued modems? 

 

If the modem is in bridge mode (we are unable to access because it is your equipment), then I would suggest replacing the modem.  Either choose one that is capable up to 300Mbps on our network for your 200Mbps service, or you can get a free modem at a Spectrum store.  Since you have your own router already, you would just want the Spectrum modem in bridge mode.  You would still manage your network and wireless with the router.   

 

If you are reluctant to exchange the modem, you can also look for loose or corroded connections and splitters that are either malfunctioning or not terminated.  Last, ensure the VPN connection is over an ethernet connection.  Wireless VPN can be impacted by ingress from other signals, like cell phone signals.    

 

All in-home connections, coax and splitters were confirmed good last month

by a Spectrum tech as I mentioned in my IP. 

 

Hope this helps.  Let us know if you have other questions.   

 

For direct support, please contact us at: 

 

 


 

Community Manager

Re: SYNC Timing Failures, Fail to Acquire FEC, Unusual Power Levels, Work VPN Dropouts

Power levels reference SNR or signal to noise ratio.  During one test, the noise level was high, during another test, the noise level was low.  It is relatively normal, keeping in mind that electromagnetic interference can interrupt the signal.  The most common culprits are common appliances like microwaves, cordless phones and baby monitors.

 

If you are getting a new Spectrum modem, you can request to have it set in bridge mode.  This way, it will act as a pass through and the router will do all the work of addressing.  It may require a call in to support after you get it home.  Otherwise, I believe the Zoom modem has an online manual.  It should outline the steps to check if it is in bridge mode.  Check back and let us know if you get a new modem and if it resolves the issue! 

Highlighted
Helper

Re: SYNC Timing Failures, Fail to Acquire FEC, Unusual Power Levels, Work VPN Dropouts


@KenH99 wrote:

Does Spectrum disable customer access to connection stats and logs on their issued modems? 

 


 


Some modems have the stats pages disabled...notably the new Spectrum-branded DOCSIS 3.1 modems made by Hitron (E31N2V1) or Technicolor (E31T2V1). There is a Ubee version (E31U2V1) that does allow access.