Our broadband connection keeps dropping

[Keeley1998]

Internet keeps dropping, looked at the log for the router and they all appear to be critical Sync failures:

18/07/2021 13:06:1	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 13:05:38	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 12:59:23	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 12:49:46	notice	LAN login Success;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 12:48:41	Warning!	LAN login FAILED : Incorrect Username / Password / ConnectionType;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 12:44:48	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 12:44:8	Error	DHCP RENEW WARNING - Field invalid in response v4 option;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 12:36:54	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 12:32:11	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 12:18:17	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 12:17:26	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 11:11:21	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 11:10:27	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 10:58:26	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 10:57:40	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 10:52:26	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 10:50:41	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
17/07/2021 19:51:34	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
17/07/2021 19:26:54	critical	No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
17/07/2021 19:17:39	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

Would anyone be able to let me know how to get this fixed? It's been frustrating where it's been dropping out so often.

[Tudor]

Please post the up/downstream stats.

[Keeley1998]

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

1	138750000	4.1	40	256 qam	1
2	146750000	3.5	38	256 qam	2
3	154750000	3	40	256 qam	3
4	162750000	2.7	40	256 qam	4
5	170750000	2.9	39	256 qam	5
6	178750000	2.5	40	256 qam	6
7	186750000	2.2	40	256 qam	7
8	194750000	2	40	256 qam	8
9	202750000	1.7	40	256 qam	9
10	210750000	1.2	40	256 qam	10
11	218750000	0.9	40	256 qam	11
12	226750000	0	38	256 qam	12
13	234750000	-0.4	40	256 qam	13
14	242750000	-0.2	38	256 qam	14
15	250750000	0.7	40	256 qam	15
16	258750000	0.7	40	256 qam	16
17	266750000	0.7	40	256 qam	17
18	274750000	0.5	40	256 qam	18
19	282750000	0.9	40	256 qam	19
20	290750000	0.9	40	256 qam	20
21	298750000	1	40	256 qam	21
22	306750000	0.7	40	256 qam	22
23	314750000	0.7	40	256 qam	23
24	322750000	0.5	40	256 qam	24

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

1	Locked	40.3	17937786	20319298
2	Locked	38.9	12738919	1147286
3	Locked	40.9	1818395	351282
4	Locked	40.3	2724993	468396
5	Locked	39.3	1565821	290953
6	Locked	40.3	1311347	228431
7	Locked	40.3	1284857	222229
8	Locked	40.3	1528263	321228
9	Locked	40.9	1159374	242110
10	Locked	40.3	772869	63067
11	Locked	40.3	938674	99654
12	Locked	38.9	1508902	252488
13	Locked	40.3	1482373	219613
14	Locked	38.9	706683	48680
15	Locked	40.3	220676	3584
16	Locked	40.3	165184	2947
17	Locked	40.9	275251	11559
18	Locked	40.3	404190	45588
19	Locked	40.3	442340	24430
20	Locked	40.3	300464	4044
21	Locked	40.3	173300	1560
22	Locked	40.3	93225	20
23	Locked	40.3	147412	258
24	Locked	40.9	213189	12094

Upstream bonded channels

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

1	25800099	43.8	5120	64 qam	6
2	46200000	45.8	5120	64 qam	3
3	39400000	44.8	5120	64 qam	4
4	32599985	44.5	5120	64 qam	5

Upstream bonded channels

Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts

1	ATDMA	0	0	9	0
2	ATDMA	0	0	8	0
3	ATDMA	0	0	15	0
4	ATDMA	0	0	17	0

Thanks for looking at this!

[Tudor · Accepted solution]

Lots of upstream T3’s are not good, Pre & Post RS errors are high, but they are since the hub was last power cycled. So please power cycle the hub and post a new set of stats after a few hours. You will probably need a technician’s visit to rectify the problem as it looks like noise ingress.

[Keeley1998]

Only been about an hour since power cycling but plenty of drops since then - new stats below:

Downstream bonded channels

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

1	138750000	3.7	37	256 qam	1
2	146750000	3	36	256 qam	2
3	154750000	2.7	36	256 qam	3
4	162750000	2.5	36	256 qam	4
5	170750000	2.5	37	256 qam	5
6	178750000	2.2	37	256 qam	6
7	186750000	1.9	38	256 qam	7
8	194750000	1.7	38	256 qam	8
9	202750000	1.4	38	256 qam	9
10	210750000	1	38	256 qam	10
11	218750000	0.5	40	256 qam	11
12	226750000	0	38	256 qam	12
13	234750000	-0.5	40	256 qam	13
14	242750000	-0.4	38	256 qam	14
15	250750000	0.4	40	256 qam	15
16	258750000	0.2	40	256 qam	16
17	266750000	0.4	40	256 qam	17
18	274750000	0.2	40	256 qam	18
19	282750000	0.5	40	256 qam	19
20	290750000	0.5	40	256 qam	20
21	298750000	0.5	40	256 qam	21
22	306750000	0.2	40	256 qam	22
23	314750000	0.2	40	256 qam	23
24	322750000	0.2	40	256 qam	24

Downstream bonded channels

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

1	Locked	37.9	1611862	385600
2	Locked	36.3	2958953	208223
3	Locked	36.3	3146048	294240
4	Locked	36.6	1522326	595803
5	Locked	37	2550042	450477
6	Locked	37.9	1803681	202788
7	Locked	38.9	1359058	9116
8	Locked	38.9	246265	1803
9	Locked	38.9	20587	1617
10	Locked	38.9	10071	464
11	Locked	40.3	10385	289
12	Locked	38.9	30504	4
13	Locked	40.3	46973	0
14	Locked	38.9	1761	0
15	Locked	40.3	103	0
16	Locked	40.3	32	0
17	Locked	40.3	12	0
18	Locked	40.9	10	0
19	Locked	40.3	2	0
20	Locked	40.3	5	0
21	Locked	40.3	6	0
22	Locked	40.3	5	0
23	Locked	40.3	8	0
24	Locked	40.3	6	0

Upstream bonded channels

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

1	25800000	44.5	5120	64 qam	6
2	46200000	46.3	5120	64 qam	3
3	39400069	45.5	5120	64 qam	4
4	32599990	45.3	5120	64 qam	5

Upstream bonded channels

Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts

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

Network Log

Time Priority Description

18/07/2021 18:28:18	notice	LAN login Success;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 17:54:25	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 17:53:42	critical	No Ranging Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
18/07/2021 17:52:22	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;

Thanks again for your advice - we will be getting in touch with VM tomorrow!

[Tudor]

Yep, you have got real problems. Phone customer services and report the issue or wait for a VM staff member on the board to get to your post.

[Hayley_S]

Hello @Keeley1998.

Welcome to the community page, thank you for posting on here.

I am sorry that your broadband keeps dropping its connection.

Please can you tell me if you have call us since you made this post? Or if you are still in need of help.

Look forward to your response.