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sweetgerald's avatar
sweetgerald
Aspirant
Sep 21, 2022

RBR750 router with CM1200 modem - unpredictable and intermittent network speed drops

Hi Posting this here because I'm at a loss for where to go next. For period of 6 weeks I've experienced network issues where download speeds will drop to single digit Mbps or less. Sometimes complet...
FURRYe38's avatar
FURRYe38
Guru - Experienced User
Sep 21, 2022

Modem:

Please post a copy and paste of the modems connection status and event log page.
https://kb.netgear.com/30007/How-do-I-obtain-the-cable-connection-information-from-a-NETGEAR-cable-modem-modem-router
https://kb.netgear.com/30008/How-do-I-view-or-clear-the-event-logs-on-my-NETGEAR-cable-modem-or-modem-router

 

Be sure your using a good quality LAN cable between the modem and router. CAT6 is recommended. 

Be sure there are no coax cable line splitters in the between the modem and ISP service box. 
Be sure your using good quality RG6 coax cable up to the modem. 
Be sure to power OFF the modem for 1 minute then back ON.
https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Modems/m-p/1530376#M12853
https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router?article=24311
https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html

 

Orbi:

Be sure your using a good quality LAN cable between the modem and router. CAT6 is recommended. 

 

What is the size of your home? Sq Ft?
What is the distance between the router and 📡 satellite(s)? 30 feet or more is recommended in between RBR and RBS📡 to begin with depending upon building materials when wirelessly connected.
https://kb.netgear.com/31029/Where-should-I-place-my-Orbi-satellite 📡
https://kb.netgear.com/000061709/Where-should-I-place-the-Mesh-WiFi-satellite-of-my-Nighthawk-Mesh-WiFi-6-and-Tri-band-Mesh-WiFi-6-products 📡

 

What channels are you using? Auto? Try Auto and 48 on 5Ghz. Or try setting manual channel 1, 6 or 11 on 2.4Ghz and 40 to 48 channel on 5Ghz.
Any Wifi Neighbors near by? If so, how many?

 

Has a power off for 1 minute then back ON with the ISP modem and router been performed since last update?
Be sure to restart your network in this sequence:
Turn off and unplug modem.
Turn off router and computers.
Plug in and turn on modem. Wait 2 minutes for it to connect.
Turn on the router and wait 2 minutes for it to connect.
Turn on computers and rest of network.

 

Has a factory reset and setup from scratch been performed since last FW update? 

 

I just had my CM1200 online for a few weeks up until last weekend with my 8 series system. Smooth operation between these two. 

 

 

sweetgerald's avatar
sweetgerald
Aspirant
Sep 21, 2022

Event Log

  

TimePriorityDescription
Wed Sep 21 10:09:04 2022Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Tue Sep 20 23:38:34 2022Warning (5)Dynamic Range Window violation
Tue Sep 20 23:38:34 2022Warning (5)RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Tue Sep 20 23:38:31 2022Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Mon Sep 19 09:23:41 2022Notice (6)CM-STATUS message sent. Event Type Code: 5; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Mon Sep 19 09:23:20 2022Notice (6)DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Mon Sep 19 09:23:15 2022Notice (6)TLV-11 - unrecognized OID;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not EstablishedNotice (6)Honoring MDD; IP provisioning mode = IPv6
Time Not EstablishedCritical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 18 09:15:54 2022Notice (6)DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Sun Sep 18 09:15:49 2022Notice (6)TLV-11 - unrecognized OID;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not EstablishedNotice (6)Honoring MDD; IP provisioning mode = IPv6
Time Not EstablishedCritical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;
Fri Sep 09 17:36:16 2022Warning (5)Dynamic Range Window violation
Fri Sep 09 17:36:16 2022Warning (5)RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Fri Sep 09 17:36:15 2022Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Fri Sep 09 15:44:56 2022Notice (6)CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Fri Sep 09 15:44:38 2022Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Fri Sep 09 15:44:16 2022Notice (6)CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Fri Sep 09 15:44:06 2022Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 18:16:12 2022Notice (6)CM-STATUS message sent. Event Type Code: 24; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 18:15:43 2022Notice (6)CM-STATUS message sent. Event Type Code: 16; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 18:12:40 2022Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 09:50:15 2022Notice (6)CM-STATUS message sent. Event Type Code: 5; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 09:49:55 2022Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 09:49:45 2022Notice (6)CM-STATUS message sent. Event Type Code: 5; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 09:49:24 2022Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 09:48:55 2022Critical (3)No Ranging Response received - T3 time-out;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 09:48:48 2022Notice (6)DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 09:48:47 2022Notice (6)TLV-11 - unrecognized OID;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 09:48:39 2022Notice (6)Honoring MDD; IP provisioning mode = IPv6
Wed Sep 07 09:48:06 2022Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 09:47:28 2022Warning (5)MDD message timeout;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 09:47:27 2022Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 09:47:18 2022Notice (6)CM-STATUS message sent. Event Type Code: 5; Chan ID: 193; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 09:47:16 2022Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 09:46:35 2022Critical (3)No Ranging Response received - T3 time-out;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 09:46:29 2022Notice (6)DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Wed Sep 07 09:46:24 2022Notice (6)TLV-11 - unrecognized OID;CM-MAC=9c:c9:eb:34:e4:a0;CMTS-MAC=00:90:f0:29:00:00;CM-QOS=1.1;CM-VER=3.1;
Time Not EstablishedNotice (6)Honoring MDD; IP provisioning mode = IPv6
  • FURRYe38's avatar
    FURRYe38
    Guru - Experienced User
    Sep 21, 2022

    A few Correctables however not bad. Those could be a slight cable issue, bad connector or fitting or maybe a splitter. 

    I see Criticals that the ISP could look into. Check those warnings as well. 

    • sweetgerald's avatar
      sweetgerald
      Aspirant
      Sep 21, 2022

      Can you elaborate on what I'm looking into with regard to criticals or warnings? Sorry - not sure what I'm looking at myself.

       

      Xfinity has claimed there is no signal issue after 2 technician visits - during which time, each of them made cable adjustments inside or outside the house. Just looking for what ammo I might need to bring to show they're the source of any issue.

       

      Does that log indicate anything that might be a source of my symptoms? I see warnings and criticals from last night, 9/20 around 11:30pm, which does correspond to when I was completely unable to connect to online access on an Xbox game.

       

      Thanks, I appreciate the fast replies.

      • plemans's avatar
        plemans
        Guru - Experienced User
        Sep 21, 2022

        According to your logs, your still having issues. 

        You're having t3 errors, dynamic range window violations, and multicast issues. 

        One thing to consider is that when you open the cable connections page, it shows what is going on at the time you open it. 

        The range window violations are when you're power is going out of spec (and by a bit). 

        So something is causing either the power to drop or increase beyond whats supports.