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constant CMTS sync issues with Cable Modem

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constant CMTS sync issues with Cable Modem

I have been this nagging issue for a long time where my cable modem keeps losing sync with CMTS connection keeps dropping causing a modem reset.

I have called Xfinity technicians many times but they were not able to resolve the issue so i am posting here. Here is the event log from my Netgear cable modem CM1100. It looks to me that there is something wrong with the signal quality. Also it seems like the power on downstream port is a higher than it should be. I am also not using any splitter at my home. Any help would be greatly appreciated. Is anyone else facing similar issue?

 

Downstream Bonded Channels

Channel

Lock Status

Modulation

Channel ID

Frequency

Power

SNR / MER

Unerrored Codewords

Correctable Codewords

Uncorrectable Codewords

1

Locked

QAM256

36

621000000 Hz

11.4 dBmV

40.2 dB

10484889

9

0

2

Locked

QAM256

8

447000000 Hz

11.4 dBmV

41.3 dB

9423172

0

0

3

Locked

QAM256

9

453000000 Hz

11.4 dBmV

41.1 dB

9425983

2

0

4

Locked

QAM256

10

459000000 Hz

11.5 dBmV

41.1 dB

9429598

2

0

5

Locked

QAM256

11

465000000 Hz

11.5 dBmV

41.0 dB

9433343

1

0

6

Locked

QAM256

12

471000000 Hz

11.4 dBmV

41.0 dB

9437363

1

0

7

Locked

QAM256

13

477000000 Hz

11.3 dBmV

40.9 dB

9440630

2

0

8

Locked

QAM256

14

483000000 Hz

11.2 dBmV

40.9 dB

9444600

3

0

9

Locked

QAM256

15

489000000 Hz

11.1 dBmV

40.9 dB

9448319

4

0

10

Locked

QAM256

16

495000000 Hz

11.2 dBmV

40.7 dB

9452195

1

0

11

Locked

QAM256

17

507000000 Hz

11.2 dBmV

40.7 dB

9455756

1

0

12

Locked

QAM256

18

513000000 Hz

11.2 dBmV

40.8 dB

9459403

3

0

13

Locked

QAM256

19

519000000 Hz

11.1 dBmV

40.9 dB

9463134

5

0

14

Locked

QAM256

20

525000000 Hz

11.3 dBmV

40.7 dB

9467011

1

0

15

Locked

QAM256

21

531000000 Hz

11.2 dBmV

40.8 dB

9470707

3

0

16

Locked

QAM256

22

537000000 Hz

11.0 dBmV

40.6 dB

9474213

5

0

17

Locked

QAM256

23

543000000 Hz

10.9 dBmV

40.5 dB

9478059

3

0

18

Locked

QAM256

24

549000000 Hz

10.9 dBmV

40.6 dB

9481787

6

0

19

Locked

QAM256

25

555000000 Hz

10.8 dBmV

40.6 dB

9485690

4

0

20

Locked

QAM256

26

561000000 Hz

10.7 dBmV

40.5 dB

9489502

4

0

21

Locked

QAM256

27

567000000 Hz

10.5 dBmV

40.4 dB

9493384

11

0

22

Locked

QAM256

28

573000000 Hz

10.7 dBmV

40.1 dB

9497118

7

0

23

Locked

QAM256

29

579000000 Hz

10.8 dBmV

40.2 dB

9500836

9

0

24

Locked

QAM256

30

585000000 Hz

10.8 dBmV

40.4 dB

9504544

6

0

25

Locked

QAM256

31

591000000 Hz

11.0 dBmV

40.2 dB

9508352

9

0

26

Locked

QAM256

32

597000000 Hz

11.4 dBmV

40.5 dB

9511889

9

0

27

Locked

QAM256

33

603000000 Hz

11.5 dBmV

40.4 dB

9515788

10

0

28

Locked

QAM256

34

609000000 Hz

11.5 dBmV

40.1 dB

9519516

6

0

29

Locked

QAM256

35

615000000 Hz

11.4 dBmV

40.1 dB

9523231

8

0

30

Locked

QAM256

37

627000000 Hz

11.2 dBmV

39.9 dB

9526620

11

0

31

Locked

QAM256

38

633000000 Hz

11.2 dBmV

40.0 dB

9522323

10

0

32

Not Locked

Unknown

0

0 Hz

0.0 dBmV

0.0 dB

0

0

0

 

Time

Priority

Description

2020-05-03, 13:40:36

Notice (6)

DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:01:5c:63:c0:4e;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Notice (6)

Honoring MDD; IP provisioning mode = IPv6

Time Not Established

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:01:5c:63:c0:4e;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:01:5c:63:c0:4e;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:01:5c:63:c0:4e;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:01:5c:63:c0:4e;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:01:5c:63:c0:4e;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:01:5c:63:c0:4e;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:01:5c:63:c0:4e;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:01:5c:63:c0:4e;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:01:5c:63:c0:4e;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

No Ranging Response received - T3 time-out;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:01:5c:63:c0:4e;CM-QOS=1.1;CM-VER=3.1;

Time Not Established

Critical (3)

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1;

2020-05-03, 11:45:22

Critical (3)

Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=38:94:ed:71:84:28;CMTS-MAC=00:01:5c:63:c0:4e;CM-QOS=1.1;CM-VER=3.1;