CBR750 random disconnects

Question

I have just the one CBR750 modem/router - no additional satellites, etc. Nearly every day at random times, I'll get disconnected and have to reboot the device.

I've tried reflashing the firmware (currently on V4.6.5.8_2.0.54), changed the 2.4 Ghz channel to 6, reset to factory settings and still getting the same results. My thinking is it's something with the line coming into the house (I have Xfinity). I don't have any splitters connected to the Coax. Any thoughts or suggestions or should I have Xfinity send a tech out to investigate?

I'm attaching my Event Log as well as the cable connection log.

Time	Priority	Description
Apr 11 2022 13:28:09	Notice (6)	TLV-11 - unrecognized OID
Apr 11 2022 13:28:09	Notice (6)	TLV-11 - unrecognized OID
Apr 11 2022 13:28:09	Notice (6)	TLV-11 - unrecognized OID
Apr 11 2022 13:28:09	Notice (6)	TLV-11 - unrecognized OID
Apr 11 2022 13:28:09	Notice (6)	TLV-11 - unrecognized OID
Apr 11 2022 13:28:09	Notice (6)	TLV-11 - unrecognized OID
Apr 11 2022 13:28:09	Notice (6)	TLV-11 - unrecognized OID
Apr 11 2022 13:28:09	Notice (6)	TLV-11 - unrecognized OID
Apr 11 2022 13:28:09	Critical (3)	Config File Rejected due to Invalid or Unexpected TLV 11
Apr 11 2022 13:28:26	Alert (2)	CM Certificate Error
Apr 11 2022 13:28:35	Notice (6)	CM-STATUS message sent. Event Type Code: 16
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Apr 11 2022 13:31:43	Warning (5)	MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1
Apr 11 2022 13:31:43	Notice (6)	TLV-11 - unrecognized OID
Apr 11 2022 13:31:43	Critical (3)	Config File Rejected due to Invalid or Unexpected TLV 11
Apr 11 2022 13:31:54	Warning (5)	RCS Partial Service
Apr 11 2022 13:32:03	Notice (6)	CM-STATUS message sent. Event Type Code: 23
Apr 11 2022 13:32:03	Alert (2)	CM Certificate Error
Apr 11 2022 13:32:08	Notice (6)	CM-STATUS message sent. Event Type Code: 16
Apr 11 2022 14:38:27	Alert (2)	CM Certificate Error
Apr 11 2022 14:47:27	Notice (6)	DS profile config update. DS Chan ID: 37.
Apr 11 2022 14:47:30	Notice (6)	CM-STATUS message sent. Event Type Code: 16
Apr 11 2022 14:48:56	Notice (6)	DS profile config update. DS Chan ID: 37.
Apr 11 2022 14:49:02	Notice (6)	CM-STATUS message sent. Event Type Code: 23
Apr 11 2022 14:50:23	Notice (6)	DS profile config update. DS Chan ID: 37.
Apr 11 2022 14:50:32	Notice (6)	CM-STATUS message sent. Event Type Code: 24
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Apr 11 2022 15:04:38	Warning (5)	MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1
Apr 11 2022 15:04:38	Notice (6)	TLV-11 - unrecognized OID
Apr 11 2022 15:04:38	Critical (3)	Config File Rejected due to Invalid or Unexpected TLV 11
Apr 11 2022 15:04:54	Alert (2)	CM Certificate Error
Apr 11 2022 15:04:57	Notice (6)	CM-STATUS message sent. Event Type Code: 2
Apr 11 2022 19:28:21	Warning (5)	Lost MDD Timeout
Apr 11 2022 19:28:27	Notice (6)	CM-STATUS message sent. Event Type Code: 23
Apr 12 2022 06:40:07	Notice (6)	DS profile config update. DS Chan ID: 37.
Apr 12 2022 06:40:12	Notice (6)	CM-STATUS message sent. Event Type Code: 24
Apr 12 2022 06:41:39	Notice (6)	DS profile config update. DS Chan ID: 37.
Apr 12 2022 06:41:46	Notice (6)	CM-STATUS message sent. Event Type Code: 2
Apr 12 2022 11:28:57	Warning (5)	Lost MDD Timeout
Apr 12 2022 11:28:58	Notice (6)	CM-STATUS message sent. Event Type Code: 24
Time Not Established	Critical (3)	No Ranging Response received - T3 time-out
Time Not Established	Warning (5)	RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW
Apr 12 2022 12:05:56	Warning (5)	MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1
Apr 12 2022 12:05:56	Notice (6)	TLV-11 - unrecognized OID
Apr 12 2022 12:05:56	Critical (3)	Config File Rejected due to Invalid or Unexpected TLV 11
Apr 12 2022 12:06:15	Alert (2)	CM Certificate Error
Apr 12 2022 12:06:20	Notice (6)	CM-STATUS message sent. Event Type Code: 5

FURRYe38 · Answer

For one the power levels are too low:
https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router?article=24311
&nbsp;
Something that the ISP needs to check on.&nbsp;Have the ISP check the signal and line quality UP to the modem.&nbsp;Be sure the ISP provisions the modem correctly.Be sure there are no coax cable line splitters in the between the modem and ISP service box.&nbsp;Be sure your using good quality RG6 coax cable up to the modem.&nbsp;
&nbsp;

FURRYe38 · Answer

Ok. Levels are a bit to low now. Might ask the ISP for tech to visit on site if you seem to continue to have problems. If we can get the power levels to a happy mid spot would be preferred.

FURRYe38 · Answer

What FW is loaded on the CBR?&nbsp;
&nbsp;
I see some&nbsp;Config File Rejected due to Invalid or Unexpected TLV 11 entries that the ISP needs to look in to.
&nbsp;
Please post a copy and paste of the modems connection status page.Have the ISP check the signal and line quality UP to the modem.&nbsp;Be sure the ISP provisions the modem correctly.Be sure there are no coax cable line splitters in the between the modem and ISP service box.&nbsp;Be sure your using good quality RG6 coax cable up to the modem.&nbsp;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#M12853https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router?article=24311https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html

Retired_Member · Answer

Firmware is&nbsp;V4.6.5.8_2.0.54&nbsp;Startup ProcedureProcedureStatusCommentAcquire Downstream Channel507000000 HzLockedConnectivity StateOkOperationalBoot StateOkOperationalSecurityEnabledBPI+IP Provisioning ModeHonor MDDhonorMdd(4)Downstream Bonded ChannelsChannelLock StatusModulationChannel IDFrequencyPowerSNRCorrectablesUncorrectable1LockedQAM 2562489000000 Hz-11.5 dBmV36.6 dB302LockedQAM 2563495000000 Hz-11.7 dBmV36.3 dB203LockedQAM 2564501000000 Hz-11.4 dBmV36.3 dB004LockedQAM 2565507000000 Hz-11.7 dBmV36.3 dB205LockedQAM 2566513000000 Hz-11.5 dBmV35.5 dB006LockedQAM 2567519000000 Hz-11.9 dBmV36.3 dB007LockedQAM 2568525000000 Hz-12.2 dBmV35.5 dB008LockedQAM 2569531000000 Hz-12.2 dBmV35.0 dB009LockedQAM 25610537000000 Hz-12.5 dBmV34.9 dB0010LockedQAM 25611543000000 Hz-12.5 dBmV35.5 dB0011LockedQAM 25612549000000 Hz-13.2 dBmV34.7 dB0012LockedQAM 25613555000000 Hz-13.0 dBmV35.5 dB0013LockedQAM 25614561000000 Hz-13.3 dBmV35.0 dB0014LockedQAM 25615567000000 Hz-12.7 dBmV35.7 dB0015LockedQAM 25616573000000 Hz-13.3 dBmV34.0 dB0016LockedQAM 25617579000000 Hz-13.5 dBmV34.3 dB0017LockedQAM 25618585000000 Hz-13.5 dBmV35.0 dB0018LockedQAM 25619591000000 Hz-13.7 dBmV33.8 dB0019LockedQAM 25620597000000 Hz-13.7 dBmV34.3 dB0020LockedQAM 25621603000000 Hz-14.3 dBmV34.9 dB7021LockedQAM 25622609000000 Hz-14.3 dBmV34.4 dB0022LockedQAM 25623615000000 Hz-14.8 dBmV34.4 dB11023LockedQAM 25624621000000 Hz-14.0 dBmV34.3 dB7024LockedQAM 25625627000000 Hz-14.0 dBmV33.9 dB2025LockedQAM 25626633000000 Hz-14.0 dBmV34.4 dB1026LockedQAM 25627639000000 Hz-14.4 dBmV34.3 dB0027LockedQAM 25628645000000 Hz-15.7 dBmV33.4 dB0028LockedQAM 25629651000000 Hz-15.8 dBmV33.3 dB0029LockedQAM 25630657000000 Hz-16.0 dBmV33.0 dB0030LockedQAM 25631663000000 Hz-16.4 dBmV32.9 dB2031LockedQAM 25632669000000 Hz-16.0 dBmV32.9 dB114413626332Not LockedN/AN/A0 Hz0.0 dBmV0.0 dB00Upstream Bonded ChannelsChannelLock StatusUS Channel TypeChannel IDSymbol RateFrequencyPower1LockedATDMA45120 Ksym/sec16400000 Hz45.0 dBmV2LockedATDMA35120 Ksym/sec22800000 Hz46.0 dBmV3LockedATDMA25120 Ksym/sec29200000 Hz46.5 dBmV4LockedATDMA15120 Ksym/sec35600000 Hz46.3 dBmV5LockedATDMA52560 Ksym/sec40400000 Hz47.0 dBmV6Not LockedN/AUnknown0 Ksym/sec0 Hz0.0 dBmV7Not LockedN/AUnknown0 Ksym/sec0 Hz0.0 dBmV8Not LockedN/AUnknown0 Ksym/sec0 Hz0.0 dBmVDownstream OFDM ChannelsChannelLock StatusModulation/Profile IDChannel IDFrequencyPowerSNR/MERActive SubcarrierNumber RangeUnerroredCodewordsCorrectableCodewordsUncorrectableCodewords1Locked337690000000 Hz-15.5 dBmV32.5 dB1108~29870002Not Locked000 Hz0.0 dBmV0.0 dB0~4095000Upstream OFDMA ChannelsChannelLock StatusModulation/Profile IDChannel IDFrequencyPower1Not Locked000 Hz0.0 dBmV2Not Locked000 Hz0.0 dBmV

Retired_Member · Answer

Thanks for the replies. Last night I checked behind the wall plate where the line is coming into the house. There was an old splitter and a kinked coax cable, which goes directly to the modem. I replaced the splitter and coax and I'm seeing a huge improvement in the power levels. Still not ideal, but much closer to normal ranges. So far no disconnects and the event log is clean, but I'll give it another few days to see how things look.

Startup Procedure

Procedure	Status	Comment
Acquire Downstream Channel	507000000 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	Uncorrectable
1	Locked	QAM 256	2	489000000 Hz	-5.5 dBmV	38.6 dB	5	0
2	Locked	QAM 256	3	495000000 Hz	-6.0 dBmV	38.6 dB	0	0
3	Locked	QAM 256	4	501000000 Hz	-6.0 dBmV	38.9 dB	0	0
4	Locked	QAM 256	5	507000000 Hz	-6.2 dBmV	38.6 dB	0	0
5	Locked	QAM 256	6	513000000 Hz	-5.9 dBmV	38.9 dB	0	0
6	Locked	QAM 256	7	519000000 Hz	-6.2 dBmV	38.9 dB	0	0
7	Locked	QAM 256	8	525000000 Hz	-6.5 dBmV	38.9 dB	0	0
8	Locked	QAM 256	9	531000000 Hz	-6.9 dBmV	38.6 dB	0	0
9	Locked	QAM 256	10	537000000 Hz	-7.0 dBmV	38.6 dB	0	0
10	Locked	QAM 256	11	543000000 Hz	-6.7 dBmV	38.6 dB	0	0
11	Locked	QAM 256	12	549000000 Hz	-7.4 dBmV	38.6 dB	0	0
12	Locked	QAM 256	13	555000000 Hz	-7.2 dBmV	38.6 dB	0	0
13	Locked	QAM 256	14	561000000 Hz	-7.5 dBmV	38.6 dB	0	0
14	Locked	QAM 256	15	567000000 Hz	-7.2 dBmV	38.6 dB	0	0
15	Locked	QAM 256	16	573000000 Hz	-7.5 dBmV	38.9 dB	0	0
16	Locked	QAM 256	17	579000000 Hz	-7.7 dBmV	37.6 dB	0	0
17	Locked	QAM 256	18	585000000 Hz	-7.5 dBmV	38.6 dB	0	0
18	Locked	QAM 256	19	591000000 Hz	-8.0 dBmV	38.2 dB	0	0
19	Locked	QAM 256	20	597000000 Hz	-7.7 dBmV	37.6 dB	1	0
20	Locked	QAM 256	21	603000000 Hz	-8.4 dBmV	38.6 dB	0	0
21	Locked	QAM 256	22	609000000 Hz	-8.4 dBmV	37.3 dB	0	0
22	Locked	QAM 256	23	615000000 Hz	-8.7 dBmV	37.6 dB	0	0
23	Locked	QAM 256	24	621000000 Hz	-8.5 dBmV	37.6 dB	3	0
24	Locked	QAM 256	25	627000000 Hz	-8.4 dBmV	37.6 dB	19	36
25	Locked	QAM 256	26	633000000 Hz	-8.5 dBmV	37.6 dB	8	41
26	Locked	QAM 256	27	639000000 Hz	-8.7 dBmV	37.6 dB	8	43
27	Locked	QAM 256	28	645000000 Hz	-9.5 dBmV	37.6 dB	6	45
28	Locked	QAM 256	29	651000000 Hz	-9.9 dBmV	37.3 dB	6	45
29	Locked	QAM 256	30	657000000 Hz	-10.4 dBmV	37.3 dB	6	43
30	Locked	QAM 256	31	663000000 Hz	-10.7 dBmV	36.6 dB	10	41
31	Locked	QAM 256	32	669000000 Hz	-10.2 dBmV	36.6 dB	19	36
32	Not Locked	N/A	N/A	0 Hz	0.0 dBmV	0.0 dB	0	0

Upstream Bonded Channels

Channel	Lock Status	US Channel Type	Channel ID	Symbol Rate	Frequency	Power
1	Locked	ATDMA	4	5120 Ksym/sec	16400000 Hz	40.5 dBmV
2	Locked	ATDMA	3	5120 Ksym/sec	22800000 Hz	40.8 dBmV
3	Locked	ATDMA	2	5120 Ksym/sec	29200000 Hz	41.0 dBmV
4	Locked	ATDMA	1	5120 Ksym/sec	35600000 Hz	41.8 dBmV
5	Locked	ATDMA	5	2560 Ksym/sec	40400000 Hz	42.0 dBmV
6	Not Locked	N/A	Unknown	0 Ksym/sec	0 Hz	0.0 dBmV
7	Not Locked	N/A	Unknown	0 Ksym/sec	0 Hz	0.0 dBmV
8	Not Locked	N/A	Unknown	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	3	37	690000000 Hz	-9.5 dBmV	37.7 dB	1108~2987	0	0	0
2	Not Locked	0	0	0 Hz	0.0 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	0.0 dBmV
2	Not Locked	0	0	0 Hz	0.0 dBmV

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CBR750 random disconnects

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