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

[sweetgerald]

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 completely 0 down. Symptoms are usually that some streaming service is buffering or my work laptop starts spinning on a page, or slack messaging or emails cannot send or receive. When I've noticed this, I quickly hit a speed test (fast dot com, or speakeasy speed test usually) which confirms single digit speeds... briefly, but then sometimes within seconds or a minute or two (after doing a couple speed tests), the wifi speed is then reading several hundred down again.

I've also done speed tests within the router admin interface. A couple times, it has shown a message indicating it couldn't receive anything from the modem, or something to that effect. 

Xfinity is my ISP. I pay for 900Mbps down, 20 up. (The upload speed never seems to be affected at least via speed test).

Orbi RBR750 router with 1 satellite, firmware version V4.6.9.11_2.3.5

Nighthawk CM1200 modem (I don't know how to check firmware version of this)

Have had this configuration for almost 8 months with no issue, before this has started happening for the past 6 weeks.

I've had Xfinity out twice. First time, the tech reconfigured some cabling outdoors after detecting "interference". Second time, the tech reconfigured some cabling indoors after detecting "interference". Both times, after a period of prolonged disconnect while they were working on the cabling, the network was stable as expected for days, and in the second case, a couple weeks. Now I'm noticing it again. Xfinity support this time detected no signal issues from their remote testing, and suggested the modem needs a firmware update, and doesn't want to send a tech out again. Per the NetGear site (and confirmed, by calling NetGear support) that Xfinity is supposed to manage firmware updates for this modem. Is that correct? I informed the representative as such, and his response was to ask NetGear support because "they'll know what to do." I don't want to necessarily pay for a NetGear technical support contract until I have exhausted all other options, or I'm convinced they'll actually be able to help. The rep I spoke with from NetGear had me look at the lights on the modem as a way of determining if the hardware was working properly. Surprise, it was, according to green lights.

I've made sure the modem is connected directly to wall power, just in case there was a faulty power supply issue in the surge protector I had been using for 8 months without issue. The router is still plugged into a power strip, if that matters. I'm beginning to wonder if there is indeed an issue with the modem. 

Thanks

G

[sweetgerald]

I should note, I'm not exactly well versed in networking and configuration. I know enough that I can work my way around what is needed if anyone can provide some guidance. 

Not sure if I put this in the first post, but I have noticed the worst of network degradation later in the evening (after 10:00pm EST) when on more than one occasion I could not use the Xbox (hard wired to the router) online and another where Netflix (streaming on the TV via wifi) was constantly stopping to buffer. 

Those are the worst cases of this. I work from home, so constantly on the network. During the day I'll see periodic drops in speed, sometimes as long as 5-10 minutes. Sometimes just 10-15 seconds. 

No pattern. No predictability.

[FURRYe38]

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-m...
https://kb.netgear.com/30008/How-do-I-view-or-clear-the-event-logs-on-my-NETGEAR-cable-modem-or-mode...

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-Mod...
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-W... 📡

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]

Cable Connection:

Frequency start Value

This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.

Starting Frequency

Startup Procedure

Procedure	Status	Comment
Acquire Downstream Channel	423000000 Hz	Locked
Connectivity State	OK	Operational
Boot State	OK	Operational
Security	Enabled	BPI+
IP Provisioning Mode	Honor MDD	honorMdd(4)

Downstream Bonded Channels

Channel	Lock Status	Modulation	Channel ID	Frequency	Power	SNR	Correctables	Uncorrectables
1	Locked	QAM256	4	423000000 Hz	1.6 dBmV	43.5 dB	0	0
2	Locked	QAM256	1	405000000 Hz	2.5 dBmV	44 dB	0	0
3	Locked	QAM256	2	411000000 Hz	2.4 dBmV	43.8 dB	0	0
4	Locked	QAM256	3	417000000 Hz	2 dBmV	43.7 dB	0	0
5	Locked	QAM256	5	429000000 Hz	1.4 dBmV	43.3 dB	1	0
6	Locked	QAM256	6	435000000 Hz	1.2 dBmV	43.2 dB	2	0
7	Locked	QAM256	7	441000000 Hz	1 dBmV	43.1 dB	1	0
8	Locked	QAM256	8	447000000 Hz	1 dBmV	43.1 dB	2	0
9	Locked	QAM256	9	453000000 Hz	1.1 dBmV	43.1 dB	0	0
10	Locked	QAM256	10	459000000 Hz	1.1 dBmV	43.1 dB	0	0
11	Locked	QAM256	11	465000000 Hz	1.1 dBmV	43 dB	0	0
12	Locked	QAM256	12	471000000 Hz	1.1 dBmV	43 dB	0	0
13	Locked	QAM256	13	477000000 Hz	1 dBmV	42.9 dB	0	0
14	Locked	QAM256	14	483000000 Hz	0.9 dBmV	42.9 dB	1	0
15	Locked	QAM256	15	489000000 Hz	1 dBmV	42.8 dB	2	0
16	Locked	QAM256	16	495000000 Hz	0.9 dBmV	42.8 dB	2	0
17	Locked	QAM256	17	507000000 Hz	0.6 dBmV	42.5 dB	2	0
18	Locked	QAM256	18	513000000 Hz	0.5 dBmV	42.5 dB	1	0
19	Locked	QAM256	19	519000000 Hz	0.4 dBmV	42.5 dB	0	0
20	Locked	QAM256	20	525000000 Hz	0.3 dBmV	42.4 dB	1	0
21	Locked	QAM256	21	531000000 Hz	0.2 dBmV	42.3 dB	2	0
22	Locked	QAM256	22	537000000 Hz	0.2 dBmV	42.3 dB	3	0
23	Locked	QAM256	23	543000000 Hz	0.2 dBmV	42.4 dB	0	0
24	Locked	QAM256	24	549000000 Hz	0.2 dBmV	42.4 dB	2	0
25	Locked	QAM256	25	555000000 Hz	0.3 dBmV	42.5 dB	3	0
26	Locked	QAM256	26	561000000 Hz	0.4 dBmV	42.5 dB	2	0
27	Locked	QAM256	27	567000000 Hz	0.5 dBmV	42.5 dB	2	0
28	Locked	QAM256	28	573000000 Hz	0.5 dBmV	42.6 dB	3	0
29	Locked	QAM256	29	579000000 Hz	0.5 dBmV	42.6 dB	0	0
30	Locked	QAM256	30	585000000 Hz	0.4 dBmV	42.6 dB	1	0
31	Locked	QAM256	31	591000000 Hz	0.5 dBmV	42.7 dB	1	0
32	Locked	QAM256	32	597000000 Hz	0.5 dBmV	42.6 dB	0	0

Upstream Bonded Channels

Channel	Lock Status	US Channel Type	Channel ID	Symbol Rate	Frequency	Power
1	Locked	ATDMA	1	5120 Ksym/sec	35600000 Hz	50.8 dBmV
2	Locked	ATDMA	2	5120 Ksym/sec	29200000 Hz	50.3 dBmV
3	Locked	ATDMA	3	5120 Ksym/sec	22800000 Hz	49.8 dBmV
4	Locked	ATDMA	4	5120 Ksym/sec	16400000 Hz	49.5 dBmV
5	Not Locked	Unknown	0	0 Ksym/sec	0 Hz	0.0 dBmV
6	Not Locked	Unknown	0	0 Ksym/sec	0 Hz	0.0 dBmV
7	Not Locked	Unknown	0	0 Ksym/sec	0 Hz	0.0 dBmV
8	Not Locked	Unknown	0	0 Ksym/sec	0 Hz	0.0 dBmV

Downstream OFDM Channels

Channel	Lock Status	Modulation / Profile ID	Channel ID	Frequency	Power	SNR / MER	Active Subcarrier Number Range	Unerrored Codewords	Correctable Codewords	Uncorrectable Codewords
1	Locked	0 ,1 ,2 ,3	193	678000000 Hz	-3.2 dBmV	40.5 dB	1108 ~ 2987	600103421	353012746	329
2	Not Locked	0	0	0 Hz	0 dBmV	0.0 dB	0 ~ 4095	0	0	0

Upstream OFDMA Channels

Channel	Lock Status	Modulation / Profile ID	Channel ID	Frequency	Power
1	Not Locked	0	0	0 Hz	0 dBmV
2	Not Locked	0	0	0 Hz	0 dBmV

Extended Upstream Transmit PowerEnable Extended Upstream Transmit Power

Current System Time:Wed Sep 21 10:06:34 2022System Up Time:2 days 00:43:54

[sweetgerald]

Event Log

Time	Priority	Description
Wed Sep 21 10:09:04 2022	Critical (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 2022	Warning (5)	Dynamic Range Window violation
Tue Sep 20 23:38:34 2022	Warning (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 2022	Critical (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 2022	Notice (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 2022	Notice (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 2022	Notice (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 Established	Notice (6)	Honoring MDD; IP provisioning mode = IPv6
Time Not Established	Critical (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 2022	Notice (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 2022	Notice (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 Established	Notice (6)	Honoring MDD; IP provisioning mode = IPv6
Time Not Established	Critical (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 2022	Warning (5)	Dynamic Range Window violation
Fri Sep 09 17:36:16 2022	Warning (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 2022	Critical (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 2022	Notice (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 2022	Critical (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 2022	Notice (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 2022	Critical (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 2022	Notice (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 2022	Notice (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 2022	Critical (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 2022	Notice (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 2022	Critical (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 2022	Notice (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 2022	Critical (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 2022	Critical (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 2022	Notice (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 2022	Notice (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 2022	Notice (6)	Honoring MDD; IP provisioning mode = IPv6
Wed Sep 07 09:48:06 2022	Critical (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 2022	Warning (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 2022	Critical (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 2022	Notice (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 2022	Critical (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 2022	Critical (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 2022	Notice (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 2022	Notice (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 Established	Notice (6)	Honoring MDD; IP provisioning mode = IPv6

[FURRYe38]

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]

Regarding cables:

• using the LAN cables that came with the hardware (modem/router). 
• no splitters as far as I know, from the ISP box to the modem (Xfinity tech did bypass some old stuff from previous homeowner's installation, on the morning of 9/7).
• Xfinity tech said the coax running up to modem was functioning well - it's in an enclosed finished room so I dont have easy access to replace anyway.

Regarding power:

• I've power cycled modem/router many times in the past month (including after firmware updates)

Regarding home details

• 2600 sqft, spread across 3 stories. Roughly 900 sqft/floor
• router and satellite are on different floors, opposite corners of the square-shaped house
• far enough away from other houses that I cannot pick up anyone else's wifi, if that is what you mean by wifi neighbors

Regarding configuration:

• using out of the box channels (not familiar with it enough to have changed anything). 
• I have not power cycled again since I noticed there was a satellite firmware update this morning, that I had not noticed before. Just updated the satellite RBS750 to same firmware as the router.
• i have not done a factory reset and scratch setup since I had it configured and set up initially 8 months ago. Thought about it, but there's never a convenient time to do it.

[sweetgerald]

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.

[FURRYe38]

---

@sweetgerald wrote:

Regarding cables:

• using the LAN cables that came with the hardware (modem/router). <CAT6 is recommended.
• no splitters as far as I know, from the ISP box to the modem (Xfinity tech did bypass some old stuff from previous homeowner's installation, on the morning of 9/7).
• Xfinity tech said the coax running up to modem was functioning well - it's in an enclosed finished room so I dont have easy access to replace anyway.

Regarding power:

• I've power cycled modem/router many times in the past month (including after firmware updates)

Regarding home details

• 2600 sqft, spread across 3 stories. Roughly 900 sqft/floor
• router and satellite are on different floors, opposite corners of the square-shaped house, <What is the distance between the RBR and RBS?
• far enough away from other houses that I cannot pick up anyone else's wifi, if that is what you mean by wifi neighbors

Regarding configuration:

• using out of the box channels (not familiar with it enough to have changed anything). <Try setting channel 1 and 40 on the RBR. Also set 40Mhz only Under Advanced Tab/Advanced Settings/Wireless Settings. I would also maybe set the power to 50% as well. 
• I have not power cycled again since I noticed there was a satellite firmware update this morning, that I had not noticed before. Just updated the satellite RBS750 to same firmware as the router. <Be sure that if FW updates are available that the RBS set updated first then the RBR lastly.
• i have not done a factory reset and scratch setup since I had it configured and set up initially 8 months ago. Thought about it, but there's never a convenient time to do it. <I recommend giving this a try on the entire system and setup from scratch. 
• Ensure the laptops wifi and ethernet adapter drivers are fully up to date as well. 

---

[plemans]

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. 

[sweetgerald]

@FURRYe38 

• will look into CAT6 if needed
• distance between RBR and RBS is about 35 ft in the horizontal plane, and about 6 ft in the vertical plane, on different floors, opposite corners of the house. So let's just assume a bit over 35 if my trigonometry is right.
• what will setting channels do?
• i just generally do the fw updates when the orbi app presents them to me
• Can do a full system reset if there are no other leads to pursue first
• regarding drivers - i'm also seeing the same symptom on all devices simultaneously. Phones, laptop, game console, tv, streaming sticks. It seems unlikely it's a device issue.

@plemans 

• I assume you  mean power to mean the signal coming from the ISP into the modem, rather than "electrical" power to the hardware, correct?
• Both Xfinity techs noted an unusually high signal coming from the pole to the house, but both techs did some cabling rearrangement that they suggested would resolve the issue. The second tech did say he'd create a ticket to have someone look at something at the pole, but that is outside the scope of me hearing back from Xfinity about.
• Is there a specific log error or warning I can cite to Xfinity for support? Or is this something to address with my hardware? 

[FURRYe38]

---

@sweetgerald wrote:

@FURRYe38 

• will look into CAT6 if needed
• distance between RBR and RBS is about 35 ft in the horizontal plane, and about 6 ft in the vertical plane, on different floors, opposite corners of the house. So let's just assume a bit over 35 if my trigonometry is right.
• what will setting channels do? <Keeps all devices to one channel since there is no other wifi neighbors using same channels and makes it easier for devices to know what there connecting to all the time using manual channels. Something I've been doing for years. 
• i just generally do the fw updates when the orbi app presents them to me <I recommend using the RBS web page and RBRs web page to manually update FW. Seen odd problems with the Orib app not correctly updating the system or getting the sequence wrong and updating the RBR and not the RBS thust he RBS gets out of sync with the RBR FW versions. You might try a full on re-load of FW using a wired PC and web browser, then power OFF for 1 minute then back ON.  
• Can do a full system reset if there are no other leads to pursue first
• regarding drivers - i'm also seeing the same symptom on all devices simultaneously. Phones, laptop, game console, tv, streaming sticks. It seems unlikely it's a device issue.

• Yes lets get the modem fully working first, then focus on the Orbi system.

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[sweetgerald]

Ok thanks @FURRYe38. What are my next steps toward getting the modem working, if it is the problem? 

The RBR and RBS are on the same FW version now, as far as I know. Those other settings you mentioned are all related to the router, correct?

@plemans suggested the errors/warnings may be worth looking into? If I understand correctly, the Cable Connection view of the modem is showing me a snapshot of power/snr/etc. at that moment in time (presently the network is behaving as expected). Should I wait until the symptoms occur again, and at that point check the Cable Connection view for power levels/snr levels/etc.?

[plemans]

correct, power on the coax line. 

it could sure be something from the pole causing it. Even something simple as a not tight enough connector on their end. 

[sweetgerald]

Is the Correctable Codewords of Downstream ofdm channels in red below of any meaning to me in this situation? Apologies, since I don't know what I'm looking at/for. 

I guess I'll continue monitoring the occurrences, and try to check the modem's connection page for power levels/monitor error logs for a while, and reach out to Xfinity if there are continued issues? 

Oddly enough, I just started to call Xfinity customer support, and their automated message suggested there was work being done an outage for my address, and I couldnt get an agent until that was resolved. I never experienced any outage today, outside of a small drop for a few minutes this morning. 

Downstream OFDM Channels

Channel Lock Status Modulation / Profile ID Channel ID Frequency Power SNR / MER Active Subcarrier Number Range Unerrored Codewords Correctable Codewords Uncorrectable Codewords 1 Locked 0 ,1 ,2 ,3 193 678000000 Hz -2.1 dBmV 41.1 dB 1108 ~ 2987 625850788 371332109 329 2 Not Locked 0 0 0 Hz 0 dBmV 0.0 dB 0 ~ 4095 0 0 0

[plemans]

Its more your uncorrectables and the log we're looking at. 

But if they're doing work, that could be the issue