M600 speed dropped to less than 100

[stpuk]

My M600 broadband has been working fine for months is now dropping below 100Mbps. HUB3 is in modem mode and it takes a reboot for it to go back to normal speeds but that lasts a very short while before it's back to less than 100 again.

Router has been rebooted and speed tests have been done from a wired PC and done multiple speed test sites - all report the same.

I'll post the modem logs and BQM graph below this message but any help with this would be appreciated.

Thanks

[stpuk]

Cable Modem StatusItem Status Comments

Acquired Downstream Channel (Hz)	290750000	Locked
Ranged Upstream Channel (Hz)	25800000	Locked
Provisioning State	Online

Downstream bonded channels

Channel Frequency (Hz) Power (dBmV) SNR (dB) Modulation Channel ID

1	290750000	7	40	256 qam	20
2	138750000	5.5	38	256 qam	1
3	146750000	5.4	40	256 qam	2
4	154750000	5.4	40	256 qam	3
5	162750000	5.3	40	256 qam	4
6	170750000	5.5	40	256 qam	5
7	178750000	5.5	40	256 qam	6
8	186750000	5.5	40	256 qam	7
9	194750000	5.4	40	256 qam	8
10	202750000	5.3	40	256 qam	9
11	210750000	5	40	256 qam	10
12	218750000	5	40	256 qam	11
13	226750000	4.5	38	256 qam	12
14	234750000	3.9	40	256 qam	13
15	242750000	3.7	40	256 qam	14
16	250750000	3.4	38	256 qam	15
17	258750000	4.9	38	256 qam	16
18	266750000	6	40	256 qam	17
19	274750000	6.4	40	256 qam	18
20	282750000	7	40	256 qam	19
21	298750000	7.1	40	256 qam	21
22	306750000	7.5	40	256 qam	22
23	314750000	7.5	40	256 qam	23
24	322750000	7.5	40	256 qam	24

Downstream bonded channels

Channel Locked Status RxMER (dB) Pre RS Errors Post RS Errors

1	Locked	40.9	647	3
2	Locked	38.9	1586624	267
3	Locked	40.3	1029784	308
4	Locked	40.3	665077	315
5	Locked	40.3	87077	257
6	Locked	40.3	13895	180
7	Locked	40.3	2659	139
8	Locked	40.3	936	131
9	Locked	40.9	553	125
10	Locked	40.3	514	134
11	Locked	40.3	501	116
12	Locked	40.9	617	108
13	Locked	38.9	653	106
14	Locked	40.9	719	81
15	Locked	40.3	743	51
16	Locked	38.9	817	39
17	Locked	38.9	716	31
18	Locked	40.9	660	12
19	Locked	40.3	671	19
20	Locked	40.9	614	5
21	Locked	40.9	636	0
22	Locked	40.9	603	13
23	Locked	40.3	622	0
24	Locked	40.3	630	0

[stpuk]

Upstream bonded channels

Channel Frequency (Hz) Power (dBmV) Symbol Rate (ksps) Modulation Channel ID

1	25800000	44	5120	64 qam	4
2	32600024	44	5120	64 qam	3
3	39400004	44	5120	64 qam	2
4	46199983	45.5	5120	64 qam	1

Upstream bonded channels

Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts

1	ATDMA	0	0	28	0
2	ATDMA	0	0	2	0
3	ATDMA	0	0	2	0
4	ATDMA	0	0	4	0

Network Log

Time Priority Description

08/01/2022 07:51:41	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
07/01/2022 07:09:7	notice	DHCP Renew - lease parameters tftp file-cmreg-vmdg505-bbt078+voc-b.cm modified;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
07/01/2022 07:09:7	Error	DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
04/01/2022 03:37:18	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/01/2022 19:09:6	notice	DHCP Renew - lease parameters tftp file-cmreg-vmdg505-bbt078+voc-b.cm modified;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
03/01/2022 19:09:6	Error	DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
01/01/2022 04:29:47	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
31/12/2021 07:09:5	notice	DHCP Renew - lease parameters tftp file-cmreg-vmdg505-bbt078+voc-b.cm modified;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
31/12/2021 07:09:5	Error	DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
30/12/2021 14:03:48	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
28/12/2021 04:15:27	notice	DHCP Renew - lease parameters tftp file-cmreg-vmdg505-bbt078+voc-b.cm modified;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

[stpuk]

[Carley_S]

Hi @stpuk.

Sorry to hear you're experiencing issues. I have located your account and check the levels and everything is in spec. I have also checked the area and there is nothing affecting you. If you have the HUB in router mode with the ethernet connected are you getting the same speed? Is the device you are using 1gbps compatible? What ethernet cable are you using? Does the speed drop when using a different port? 

[stpuk]

Hi @Carley_S

As mentioned in my initial post, this has been working absolutely fine until very recently.

A reboot of my router made no difference but as before, rebooting the HUB restored the speed back to what it should be as you can see in the speed test history below. This of course will reduce over the next 24-48 hours as it has done previously, so I suspect there is in fact something amiss on your side or there is a fault with the modem.

I've not been able to check the HUB in router mode yet but in answer to your other questions, everything is 1Gbps compatible and Cat6 cables are being used.

[David_Bn]

Good Afternoon @stpuk, can you please advise me how the service has been performing since your latest post?

Have you possibly been able to run a speed test with the hub in modem mode and using one of your Cat 6 Ethernet cables?

Kindest regards,

David_Bn

[stpuk]

Hi David

As usual it worked fine for a short while and then has reverted back to below 100Mbps. I won't be able to check it in router mode until the weekend unfortunately

[David_Bn]

Thanks for the update @stpuk, do please let us know when you've been able to give router mode a try for us

Kindest regards,

David_Bn