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Un-reliable connection - SYNC Timing Synchronization failures

For the past couple of weeks we've been experiencing regular drops in connection - pauses while watching streaming TV, disconnects from video calls, VPN connections etc.  Speedtests are fluctuating wildly.

I'm seeing lots of errors in the network logs, here's my info from this morning.  I rebooted the hub roughly 24 hours before this:

Cable Modem Status

Item

Status

Comments

Acquired Downstream Channel (Hz)

323000000

Locked

Ranged Upstream Channel (Hz)

53699909

Locked

Provisioning State

Online

 

 

 

Downstream bonded channels

Channel

Frequency (Hz)

Power (dBmV)

SNR (dB)

Modulation

Channel ID

1

323000000

2.5

38

256 qam

24

2

139000000

-0.2

37

256 qam

1

3

147000000

-0.5

37

256 qam

2

4

155000000

-0.2

37

256 qam

3

5

163000000

0

38

256 qam

4

6

171000000

0.2

38

256 qam

5

7

179000000

0.2

38

256 qam

6

8

187000000

0.2

38

256 qam

7

9

195000000

0.2

38

256 qam

8

10

203000000

0.4

38

256 qam

9

11

211000000

0.5

38

256 qam

10

12

219000000

0.5

38

256 qam

11

13

227000000

0.2

38

256 qam

12

14

235000000

0

38

256 qam

13

15

243000000

-0.5

38

256 qam

14

16

251000000

-0.2

38

256 qam

15

17

259000000

0

38

256 qam

16

18

267000000

0.5

38

256 qam

17

19

275000000

0.7

38

256 qam

18

20

283000000

0.9

38

256 qam

19

21

291000000

1.2

38

256 qam

20

22

299000000

1.7

38

256 qam

21

23

307000000

2

38

256 qam

22

24

315000000

2.4

40

256 qam

23




Downstream bonded channels

Channel

Locked Status

RxMER (dB)

Pre RS Errors

Post RS Errors

1

Locked

38.9

1942479

1337328

2

Locked

37.6

5599973

4216171

3

Locked

37.6

5329292

3934032

4

Locked

37.3

5051173

3713771

5

Locked

38.6

4791071

3486719

6

Locked

38.6

4526622

3258277

7

Locked

38.6

4324950

3063980

8

Locked

38.6

4106779

2872818

9

Locked

38.6

3908660

2715004

10

Locked

38.6

3710157

2550242

11

Locked

38.6

3558012

2445415

12

Locked

38.6

3375432

2298166

13

Locked

38.6

3229499

2176898

14

Locked

38.6

3081881

2082524

15

Locked

38.6

2934317

1984551

16

Locked

38.6

2816727

1908707

17

Locked

38.9

2693366

1809142

18

Locked

38.9

2570366

1734866

19

Locked

38.6

2460735

1663918

20

Locked

38.9

2359552

1601762

21

Locked

38.9

2273010

1547417

22

Locked

38.6

2201326

1482295

23

Locked

38.9

2095452

1449383

24

Locked

40.3

2011437

1411247

 

Upstream bonded channels

Channel

Frequency (Hz)

Power (dBmV)

Symbol Rate (ksps)

Modulation

Channel ID

1

53699909

4.6

5120

64 qam

2

2

39400000

3.675

5120

64 qam

4

3

46200000

4.575

5120

64 qam

3

4

60299995

3.775

5120

64 qam

1




Upstream bonded channels

Channel

Channel Type

T1 Timeouts

T2 Timeouts

T3 Timeouts

T4 Timeouts

1

ATDMA

0

0

0

0

2

ATDMA

0

0

0

0

3

ATDMA

0

0

0

0

4

ATDMA

0

0

0

0

 

 

Primary Downstream Service Flow

SFID

5276

Max Traffic Rate

230000061

Max Traffic Burst

42600

Min Traffic Rate

0




Primary Upstream Service Flow

SFID

5275

Max Traffic Rate

22000061

Max Traffic Burst

42600

Min Traffic Rate

0

Max Concatenated Burst

42600

Scheduling Type

BestEffort

 

logs continued in next post...

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Re: Un-reliable connection - SYNC Timing Synchronization failures

 

Network Log

Time

Priority

Description

21/10/2020 07:56:8

Warning!

RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:56:7

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:55:12

Warning!

RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:55:10

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:46:50

Warning!

RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:46:48

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:46:36

Warning!

RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:46:36

critical

No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:46:31

Warning!

RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:46:30

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:46:27

Warning!

RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:46:23

critical

No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:46:18

Warning!

RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:46:15

critical

No Ranging Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:46:9

Warning!

RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:46:8

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:38:51

Warning!

RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:38:51

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:35:21

Warning!

RCS Partial Service;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

21/10/2020 07:35:20

critical

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.0;

 

Jamieg285_0-1603268985002.png

 

[url=https://www.thinkbroadband.com/broadband/monitoring/quality/share/581307eb6567f71a37bea0bab62457fac9179506]My Broadband Ping[/url]

 

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Message 3 of 9
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Re: Un-reliable connection - SYNC Timing Synchronization failures

I think I should also point out, I am using SuperHub 3.0 in standard mode.
The problem is affecting wired and wireless connections.
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Re: Un-reliable connection - SYNC Timing Synchronization failures

Looking at those stats and BQM, unless there’s an area issue you’ll need an engineer.

When was the hub last rebooted?


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Re: Un-reliable connection - SYNC Timing Synchronization failures

Hub was rebooted around 24 hours before those stats
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Re: Un-reliable connection - SYNC Timing Synchronization failures

Your >> Live BQM << is a mess.

Have you checked the 'Check Service Status' at the top of the page ?

If nothing is showing try phoning 0800 561 0061, this will tell you of more local issues that may be affecting your district. Be aware that it isn't a manned line.

Go round all the accessible internal and external co-ax connections and ensure that they are finger tight.

***********************************************************************************************************************************

Mike Robinson
Semi-Retired Aircraft Engineer & Computer Based Training and Learning Designer for many of the world's Military Arms.

My Broadband Ping - Mike Robbo
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Re: Un-reliable connection - SYNC Timing Synchronization failures

No issues reported in Service Status or on the phone. Checked all internal cables, no obvious problems.
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Re: Un-reliable connection - SYNC Timing Synchronization failures

Call in for an engineer visit, don't be technical; just tell them that your internet keeps cutting out.

You can either phone in (08:00 is the best time) or wait on here for a few days (6 to 7 days average) until one of the VM Forum Staff comes along.

If you wait on here Do Not bump the thread it will put it further down the VM 'to do list'.

***********************************************************************************************************************************

Mike Robinson
Semi-Retired Aircraft Engineer & Computer Based Training and Learning Designer for many of the world's Military Arms.

My Broadband Ping - Mike Robbo
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Re: Un-reliable connection - SYNC Timing Synchronization failures

Finally fixed(?), but not an easy route and shocking customer support from VM:

The online diagnostic tool detected an 'intermittent' issue and applied 'some change'.  Check back after 24 hours.

24 hours later, no improvement, but the diagnostic tool allows me to book an engineer.  Booked for 3 days time 🙂

Engineer arrives, says the signal is too high.  Takes 2x attenuators off the input cable and replaces with a different one and installs a new SH3.  All seems good for a few hours, then back to the same issues.

The online detector tool encounters errors while trying to run and doesn't complete, so can't confirm if faults found or allow me to book another engineer.

Out of desperation I call and wait for a couple of hours to speak to someone.  Support person (off-shore) makes a setting change their end and says it will be fixed.  I ask for an engineer visit just in case (that I can cancel if the problem is really fixed), but they say they can't do that unless there is fault found, which at this time there isn't.  He said the best they could do for now was make an appointment to call me back the next day to see how it was going.

The next day, issue is still present.  Appointment time for call came and went - no phone call.   I call and wait another 90mins or so before getting through to someone (again off-shore).  He tells me that there is no policy for calling customers back - meaning that one of these two is a liar.  He then proceeds to get me to change a Wi-Fi setting in the hub.  I explain the issues I am having and it's affected wired connections, so isn't a wireless issue, but he arrogantly tells me that he does this thing all the time and knows what he's doing and it will definitely fix my issue.  I started pushing back, insisting on arranging an engineer booking, at which time he simply says thank you for calling and hung up.  I have lodged a formal complaint against this guy, but unsurprisingly I've not heard anything back on that either.

Guess what - he didn't solve my issue either.   I made another call to support (earlier in the morning, but still an hour wait) and got through to someone in the UK.  No questions, no problems, he simply arranged the engineer visit. 

Engineer #2 arrives and listens to the issues.  Confirms signal is too high, but goes to the cabinet to check.  Changes slots to a lower power one (tells me there's only 2 options in that cabinet) He replaced the connectors at the same time.  He also changed all the external connectors outside the house, meaning apart from the under ground cable, everything connection from the cabinet to the hub is new. 

BQM monitor has been clear for 2 days now.  Speeds are good but not stunning, but I'll settle for stability for the time being.  PreRS Errors are all below 40 and PostRS are all at zero too.  The sync error messages have also gone. 

 

Although it seems to be working, I'm seriously un-impressed with VM customer service here, to the point where I was investigating alternative suppliers and was very close to switching away. I may still do so, but we'll see how it goes.  

 

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