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Frequent degradation of bandwidth with SB6190 modem

Regular Visitor

Frequent degradation of bandwidth with SB6190 modem

I have been having frequent degradation of bandwidth over the past month. Techs have visited and check (and replace splitters, etc) from the box at the street through to the final connection with my SB6190. Things work for several hours to a day or so (up to 179 Mbps down, 6 Mbps up with Blast Plus). Then everything drops to about 33 Mbps down, but maintaining upload (usually). When bandwidth crashes, my modem is showing at least one channel not "Locked". Here is a current status dump. Note that Channel 16 is not locked. What is this telling me?

 

Status

The statuses listed show the connection state of the cable modem. They are used by your service provider to evaluate the operation of the cable modem.

Top of Form

 

 

Startup Procedure

Procedure

Status

Comment

Acquire Downstream Channel

 

Locked

Connectivity State

OK

Operational

Boot State

OK

Operational

Configuration File

OK

 

Security

Enabled

BPI+

DOCSIS Network Access Enabled

Allowed

 

 

Downstream Bonded Channels

Channel

Lock Status

Modulation

Channel ID

Frequency

Power

SNR

Corrected

Uncorrectables

1

Locked

256QAM

13

651.00 MHz

1.80 dBmV

38.98 dB

3014410

2551449

2

Locked

256QAM

1

579.00 MHz

-1.80 dBmV

36.61 dB

1658

7138

3

Locked

256QAM

2

585.00 MHz

-1.60 dBmV

36.61 dB

866

8635

4

Locked

256QAM

3

591.00 MHz

-1.50 dBmV

37.36 dB

1101

8145

5

Locked

256QAM

4

597.00 MHz

-1.30 dBmV

36.61 dB

1531

8577

6

Locked

256QAM

5

603.00 MHz

-0.80 dBmV

36.61 dB

1460

9973

7

Locked

256QAM

6

609.00 MHz

-0.40 dBmV

37.36 dB

1405

9278

8

Locked

256QAM

7

615.00 MHz

0.00 dBmV

37.64 dB

2330

10180

9

Locked

256QAM

8

621.00 MHz

0.30 dBmV

37.36 dB

1722

9089

10

Locked

256QAM

9

627.00 MHz

0.80 dBmV

37.64 dB

1055929

1192969

11

Locked

256QAM

10

633.00 MHz

1.30 dBmV

37.64 dB

1728435

1559017

12

Locked

256QAM

11

639.00 MHz

1.60 dBmV

37.36 dB

2409227

3060600

13

Locked

256QAM

12

645.00 MHz

1.70 dBmV

37.64 dB

2275105

4102850

14

Locked

256QAM

14

657.00 MHz

2.10 dBmV

38.61 dB

6466

43926

15

Locked

256QAM

15

663.00 MHz

2.30 dBmV

38.61 dB

751526

1783555

16

Not Locked

----

16

669.00 MHz

----

----

----

----

17

Locked

256QAM

17

675.00 MHz

3.20 dBmV

38.61 dB

141724

26071

18

Locked

256QAM

18

681.00 MHz

3.40 dBmV

38.61 dB

2987573

3229222

19

Locked

256QAM

19

687.00 MHz

3.60 dBmV

38.98 dB

5766342

6323226

20

Locked

256QAM

20

693.00 MHz

3.40 dBmV

38.61 dB

7090041

8060404

21

Locked

256QAM

21

699.00 MHz

3.30 dBmV

38.98 dB

7851801

7923216

22

Locked

256QAM

22

705.00 MHz

3.30 dBmV

38.61 dB

5415296

7869400

23

Locked

256QAM

23

711.00 MHz

3.40 dBmV

38.61 dB

1361

11146

24

Locked

256QAM

24

717.00 MHz

3.40 dBmV

38.61 dB

1288

12852

25

Locked

256QAM

25

723.00 MHz

3.40 dBmV

38.60 dB

23

585

26

Locked

256QAM

26

729.00 MHz

3.40 dBmV

38.60 dB

21

602

27

Locked

256QAM

27

735.00 MHz

3.30 dBmV

38.60 dB

11

695

28

Locked

256QAM

28

741.00 MHz

3.30 dBmV

38.60 dB

17

636

29

Locked

256QAM

29

747.00 MHz

3.10 dBmV

38.20 dB

24

651

30

Locked

256QAM

30

753.00 MHz

2.70 dBmV

37.90 dB

29

643

31

Locked

256QAM

31

759.00 MHz

2.30 dBmV

38.20 dB

29

631

 

Upstream Bonded Channels

Channel

Lock Status

US Channel Type

Channel ID

Symbol Rate

Frequency

Power

1

Locked

ATDMA

2

5120 kSym/s

30.10 MHz

49.00 dBmV

2

Locked

ATDMA

4

5120 kSym/s

17.30 MHz

49.00 dBmV

3

Locked

ATDMA

3

5120 kSym/s

23.70 MHz

49.00 dBmV

4

Locked

ATDMA

1

5120 kSym/s

36.50 MHz

47.50 dBmV

 

Current System Time: Tue Apr 17 20:55:40 2018

Expert

Re: Frequent degradation of bandwidth with SB6190 modem

Hi @bobdewitt,

Since you already had a tech visit...

 

I've asked an employee to check the CMTS for real-time and historical RF signal reports from your modem. They can also check your local node/plant for any degradation or error reports. You can expect a reply in this thread. 

Regular Visitor

Re: Frequent degradation of bandwidth with SB6190 modem

Much appreciated, nerdberg! :-)

Official Employee

Re: Frequent degradation of bandwidth with SB6190 modem

Hi bobdewitt. I can assist with troubleshooting your internet speed issues. As nerdburg recommended, I'd like to start with polling the CMTS for real-time and historical RF signal reports from your modem. I can also check your local Node/Plant for any degradation or error reports. Please send me a private message and include your full name and account primary phone number so I can access your equipment.

Regular Visitor

Re: Frequent degradation of bandwidth with SB6190 modem

I sent the info that you requested via private message, ComcastJoeTru. Many thanks!