Intermittent Internet drops: SYNC Timing Synchronization failure

[Bestow]

For the past few days I've been suffering from Internet Connectivity dropouts. The dropouts can last anywhere between a few seconds, to tens of minutes and each one has a corresponding log entry in the SH3:

Time Priority Description

18/01/2024 10:48:43	notice	LAN login Success;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:43:16	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:43:16	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:43:15	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:39:12	notice	LAN login Success;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:38:42	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:38:42	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:38:13	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:38:13	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:32:44	notice	LAN login Success;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:16:37	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:16:37	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:16:33	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:16:33	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:15:40	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:15:40	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:02:36	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:02:35	critical	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 10:01:22	Warning!	RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;
18/01/2024 09:59:3	notice	LAN login Success;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

Repeated attempts to contact support via the web chat have been fruitless and useless. They don't seem to have any comprehension of what I'm talking about.

I don't really know where to go from this and I'm tearing my hair out.

[Tudor]

Please post a full sr of stats and setup a Broadband Quality Monitor and post a link to your live graph. It monitors your connection 24/7 and provides diagnosis of any underlying issues

[Bestow]

Downstream bonded channels

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

1	690250000	3.9	35	256 qam	40
2	490250000	2.2	33	256 qam	17
3	498250000	2	34	256 qam	18
4	506250000	2	34	256 qam	19
5	514250000	2.2	34	256 qam	20
6	522250000	2.5	34	256 qam	21
7	530250000	2.5	34	256 qam	22
8	538250000	2.4	34	256 qam	23
9	546250000	2.5	34	256 qam	24
10	554250000	2.7	34	256 qam	25
11	562250000	2.7	34	256 qam	26
12	570250000	2.9	34	256 qam	27
13	578250000	2.5	34	256 qam	28
14	586250000	2.5	34	256 qam	29
15	594250000	3	34	256 qam	30
16	602250000	3.2	34	256 qam	31
17	610250000	2.9	34	256 qam	32
18	618250000	2.5	35	256 qam	33
19	626250000	2.7	34	256 qam	34
20	634250000	3	35	256 qam	35
21	658250000	3	34	256 qam	36
22	666250000	3	35	256 qam	37
23	674250000	3.7	35	256 qam	38
24	682250000	4	35	256 qam	39

Downstream bonded channels

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

1	Locked	35.7	1395	20380
2	Locked	33.9	17084	20364
3	Locked	34.4	11584	20737
4	Locked	34.3	9193	20535
5	Locked	34.3	10249	20978
6	Locked	34.3	8152	20301
7	Locked	34.3	6994	20638
8	Locked	34.4	4117	20589
9	Locked	34.4	6117	20781
10	Locked	34.4	5933	20956
11	Locked	34.3	5677	19975
12	Locked	34.4	4208	20713
13	Locked	34.4	4567	20549
14	Locked	34.9	3278	20937
15	Locked	34.9	3246	21180
16	Locked	34.4	3982	20842
17	Locked	34.9	2930	20644
18	Locked	35	1720	20442
19	Locked	34.9	1693	21107
20	Locked	35	2074	21066
21	Locked	34.9	1636	20076
22	Locked	35	1605	20542
23	Locked	35	1687	21002
24	Locked	35	1566	20659

[Bestow]

Created a Monitor, but will take time to generate a picture of the situation.

Upstream bonded channels

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

1	23600000	46.8	5120	64 qam	9
2	36600000	45.8	5120	64 qam	3
3	43100000	45.8	5120	64 qam	2
4	49600000	46.3	5120	64 qam	1
5	30100000	46.3	5120	64 qam	4

Upstream bonded channels

Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts

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

[Bestow]

So here's the Monitor after running for a while. I've got an Engineer turning up tomorrow hopefully, so we'll see what they say.

[Beth_G]

Thanks for posting your BQM graph Bestow - looks like there are some periods of very poor performance there.

How did the visit go? Has your connection improved since?