Motorla Sufboard 5101/5100, Extreme lag and disconnection issues

M

Mikesta

2[H]4U
Joined
Jan 8, 2003
Messages
2,268
Recently I have been experiencing really bad latency and disconnection issues recently. I am thinking the culprit may be the modem. I am using a WNR3500L router flashed to DD-WRT, never had problems with it in the past. Has been an excellent router. Playing games is near impossible. Ping jumps from 30-80 to 1.5k-2k plus continuously. Some days the internet works just fine and others it's terrible.

This is the signal/frequency info

Frequency 93000000 Hz Locked
Signal to Noise Ratio 28 dB
Power Level -11 dBmV
The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading

Upstream Value
Channel ID 1
Frequency 27000000 Hz Ranged
Power Level 50 dBmV
Click to expand...

This is what I see in the logs.

2011-09-28 09:35:25 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:35:15 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:35:15 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:35:14 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:35:14 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:35:14 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:35:13 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:35:13 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:35:07 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:35:06 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:35:05 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:35:05 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:35:03 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:35:03 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:35:03 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:35:02 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:35:01 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:35:01 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:34:58 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:34:57 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:34:52 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:34:47 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:34:47 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:34:32 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:34:32 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:34:21 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:34:20 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:34:20 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:34:20 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:34:20 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:34:19 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:34:19 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:34:18 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:34:18 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:34:17 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:34:17 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:34:16 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
2011-09-28 09:34:16 3-Critical T002.0 SYNC Timing Synchronization failure - Failed to acquire FEC framing
2011-09-28 09:34:15 3-Critical T001.0 SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
Click to expand...

Any clues on what may be going on? I googled the issue and there seems to be no real explanation on this failure in the logs.

I just found this
%UBR900-4-FAILED_TO_ACQUIRE_SYNC: T01.0 Failed to acquire QAM/QPSK symbol timing. Error stats? Retry [dec]'s

Explanation The cable modem could not lock on to the downstream's QAM/QPSK SYNC signal This error message is DOCSIS event message T01.0, SYNC Timing Synchronization failure.

Recommended Action Check the RF plant for cabling and connector problems that could be generating noise on the downstream. If using a Cisco CMTS, you can use the show cable flap-list command to determine if other cable modems on the upstream are having problems. You can also use the show interfaces cable upstream command and examine the noise, microreflection, and uncorrectable error counters to determine the level of noise on the upstream.
Click to expand...

Bad cabling? Coaxial or CAT5?
 
Last edited:
Have you called your cable company? They can run line quality tests.
 
I will be calling them first thing in the morning, I was going to call them today to replace the modem but I wanted to research the problem before they come out here having to replace the modem ending up with the same lag before. The cable company out here "Northland" is very slack when it comes to technical support and on-site help. :/

Also tomorrow I am going to trace the cabling through the house to see the condition of the splitters. This is a 1970's approximately house so the coaxial cabling was ran after the house was built cause the main thing that tells me that is the coaxial cable that is hanging from the ceiling from one corner of my room from a hole drilled in the ceiling definitely looks to be done by the landlord or he paid someone to do this. Not the usual coaxial location you'd think of lol.

Any idea on if my signal to noise and power levels are normal?
 
Last edited:
Mikesta said:
Any idea on if my signal to noise and power levels are normal?
Click to expand...

Those values are NOT normal. For a power level of -11dbmv (which is kinda low anyway) your SNR should still be higher than 28db. At around ~30db connectivity can start getting spotty. This is either a cabling issue or a bad modem.
 
Ehren8879 said:
Those values are NOT normal. For a power level of -11dbmv (which is kinda low anyway) your SNR should still be higher than 28db. At around ~30db connectivity can start getting spotty. This is either a cabling issue or a bad modem.
Click to expand...

I will call the tech tomorrow. I was quite busy today. I replaced the CAT5 cable last night and reset the factory values on the modem. Seems to be working fine today, speed tests are reading 5mbps+ for our 6mbps connection, before it was reading as low as 1mbps. And the logs isn't showing the critical error anymore but as you said the values are not normal so something must be up still.

Decided to head up into the attic and check out the coaxial cabling myself. The coaxial line that is running to the modem is extended by approximately 4 different cables using male-to-male extenders. Sounds like I may have found the culprit. Coaxial cabling is cheap these days and the main line isn't that far away from where the modem is at so I have no clue why they would have done this, there is about 50-75feet of extra slack for this coaxial line sitting up there.
 
Last edited:
Mikesta said:
I will call the tech tomorrow. I was quite busy today. I replaced the CAT5 cable last night and reset the factory values on the modem. Seems to be working fine today, speed tests are reading 5mbps+ for our 6mbps connection, before it was reading as low as 1mbps. And the logs isn't showing the critical error anymore but as you said the values are not normal so something must be up still.

Decided to head up into the attic and check out the coaxial cabling myself. The coaxial line that is running to the modem is extended by approximately 4 different cables using male-to-male extenders. Sounds like I may have found the culprit. Coaxial cabling is cheap these days and the main line isn't that far away from where the modem is at so I have no clue why they would have done this, there is about 50-75feet of extra slack for this coaxial line sitting up there.
Click to expand...

The CAT5 wouldn't be to blame. What are your values reading currently?

You're right that one of those splice points could be the problem... could also be something else. If you can bypass all that garbage cable and splits and connect straight to your drop, see if that makes a difference in your power levels and especially snr. If snr improves significantly then it's definitely a cabling issue.
 
Ehren8879 said:
The CAT5 wouldn't be to blame. What are your values reading currently?

You're right that one of those splice points could be the problem... could also be something else. If you can bypass all that garbage cable and splits and connect straight to your drop, see if that makes a difference in your power levels and especially snr. If snr improves significantly then it's definitely a cabling issue.
Click to expand...

Frequency 93000000 Hz Locked
Signal to Noise Ratio 28 dB
Power Level -11 dBmV
The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading
Upstream Value
Channel ID 1
Frequency 27000000 Hz Ranged
Power Level 49 dBmV

These are the current signal values. We literally just had tech support to a reset on their end for our connection. The Cat5 cable definitely didn't help and we've been going at it back and forth with our ISP trying to get a tech out here. I haven't had a chance to order a new coaxial cable to run to our modem as of yet.

Also just to throw this in, during these extreme latency issues when running a speed test the bandwith usually puts out about .5-1.5mbps while we are paying for a 6mbps connection if this changes anything.
 
I'm sorry your isp's tech support can't see the obvious. Good luck, hope you get that tech out there.
 
I have this:
http://www.newegg.com/Product/Product.aspx?Item=N82E16825122014

I experience the same issue you're describing. Originally I called Comcast and explained my random disconnects and sudden slow speed and they started running me through everything it could be splitters etc. With work I was never able to be around for a tech to come out and just dealt with it for like 6 months. Recently I moved and left that motorola at my old location for the person staying there, wondering if maybe I just got a bad one I bought another and have been in my new apartment for approx 2 months and am getting the same errors etc.

I called comcast because I was only getting 38ish mb of my 50mb I was paying for, they did some things on there end and now I run smoothly at 55-65mb down when the connection is good. However I still got random timeouts and disconnects, and even the gateway having to be powered off and back on in order to refresh the signal. Called a tech to come out, showed him the errors and he had no clue what they meant.

Of course the issue didn't happen while he was there and he didn't have any advice for me. He said the line etc was good and when they check it from comcasts end they say I have a solid connection on the line itself. I'm about to try buying something else and see if that really is the issue but I don't know. When I get home I'll post my logs on here to compare.
 
What type of Coax cable is being used? These days you really should have RG-6 cable for runs less than 200ft, or RG-6Quad for longer or even RG-11 for really long runs. Some people cheap out and still use RG-59 which on long lengths has a lot of signal loss. But it sounds like you have too much to begin with. I would complain to your landlord and/or your ISP and see who will fix it. If neither will, get written permission from your landlord and fix it yourself. Run one continious Coax from the demarc to your modem. Install a nice faceplate on the wall to dress it up. Done. And I bet that would significantly improve the signal levels.
 
Frequency 93000000 Hz Locked
Signal to Noise Ratio 28 dB <========= This is very crappy. Tech support should have seen this and dispatched someone.
Power Level -11 dBmV <======= Acceptable range is -10 dBmV to 10 dBmV ideally.

If you're getting a good quality signal in then even a -11 should still be able to provide a 33dB or greater SNR. You can try a new coax jumper from the wall to the modem, but if that doesn't fix it Mr. Technician NEEDS to pay you a visit. It's either a bad peice of cable, a bad connector or simply a bad modem.

The 28dB SNR explains all the issues you've been seeing. FYI, I work for a cable ISP.

Edit#21

Also is your modem a 5100 or a 5101 (if you say 5120 throw it in the trash immediately) and how long have you had it?
 
Last edited:
Sorry mine is a little late. Below is what my log file is currently filled with. Not sure what it means, would be nice if someone on here knew. Thanks in advance.


Fri Oct 21 16:56:21 2011 Notice (6) TLV-11 - unrecognized OID;CM-MAC=e4:83:99:5b:b7:aa;CMTS-MAC=00:01:5c:31:29:0d;CM-QOS=1.1;CM-VER=3.0;
Time Not Established Critical (3) No Ranging Response received - T3 time-out
Thu Oct 20 06:30:00 2011 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=e4:83:99:5b:b7:aa;CMTS-MAC=00:01:5c:31:29:0d;CM-QOS=1.1;CM-VER=3.0;
Time Not Established Critical (3) No Ranging Response received - T3 time-out
Wed Oct 19 21:42:36 2011 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=e4:83:99:5b:b7:aa;CMTS-MAC=00:01:5c:31:29:0d;CM-QOS=1.1;CM-VER=3.0;
Time Not Established Critical (3) No Ranging Response received - T3 time-out
Mon Oct 17 09:52:48 2011 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=e4:83:99:5b:b7:aa;CMTS-MAC=00:01:5c:31:29:0d;CM-QOS=1.1;CM-VER=3.0;
Mon Oct 17 09:52:46 2011 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=e4:83:99:5b:b7:aa;CMTS-MAC=00:01:5c:31:29:0d;CM-QOS=1.1;CM-VER=3.0;
Mon Oct 17 09:52:35 2011 Critical (3) SYNC Timing Synchronization failure - Failed to receive MAC SYNC frame within time-out period;CM-MAC=e4:83:99:5b:b7:aa;CMTS-MAC=00:01:5c:31:29:0d;CM-QOS=1.1;CM-VER=3.0;
Time Not Established Critical (3) No Ranging Response received - T3 time-out
Sat Oct 15 15:12:54 2011 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=e4:83:99:5b:b7:aa;CMTS-MAC=00:01:5c:31:29:0d;CM-QOS=1.1;CM-VER=3.0;
Time Not Established Critical (3) No Ranging Response received - T3 time-out
Thu Oct 13 09:27:02 2011 Critical (3) No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=e4:83:99:5b:b7:aa;CMTS-MAC=00:01:5c:31:29:0d;CM-QOS=1.0;CM-VER=3.0;
Thu Oct 13 09:26:52 2011 Critical (3) No Ranging Response received - T3 time-out
Thu Oct 13 09:26:27 2011 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=e4:83:99:5b:b7:aa;CMTS-MAC=00:01:5c:31:29:0d;CM-QOS=1.1;CM-VER=3.0;
Thu Oct 13 09:25:54 2011 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=e4:83:99:5b:b7:aa;CMTS-MAC=00:01:5c:31:29:0d;CM-QOS=1.1;CM-VER=3.0;
Thu Oct 13 09:24:40 2011 Critical (3) No Ranging Response received - T3 time-out
Thu Oct 13 09:24:38 2011 Critical (3) No Maintenance Broadcasts for Ranging opportunities received - T2 time-out;CM-MAC=e4:83:99:5b:b7:aa;CMTS-MAC=00:01:5c:31:29:0d;CM-QOS=1.0;CM-VER=3.0;
Thu Oct 13 09:24:27 2011 Critical (3) No Ranging Response received - T3 time-out
 
I see a bunch of T3 and a couple T2, T4 timeout, which are are forward and return timing problems. Your cable modem is in constant communication with a CMTS (a big cable modem router). This CMTS constantly gives the modem timing intervals to talk on. When there is either a send or receive communcation problem, a timeout can result. After a certain number of timeouts a modem can shut down and reboot. I didn't notice any reboots in your logs.

Since timouts are commonly present and people ask about them often enough, I'll stick this link here:
http://www.dslreports.com/faq/13055

To get an idea of what else may be going on I need the information from the signal page.
 
Ehren8879 said:
I see a bunch of T3 and a couple T2, T4 timeout, which are are forward and return timing problems. Your cable modem is in constant communication with a CMTS (a big cable modem router). This CMTS constantly gives the modem timing intervals to talk on. When there is either a send or receive communcation problem, a timeout can result. After a certain number of timeouts a modem can shut down and reboot. I didn't notice any reboots in your logs.

Since timouts are commonly present and people ask about them often enough, I'll stick this link here:
http://www.dslreports.com/faq/13055

To get an idea of what else may be going on I need the information from the signal page.
Click to expand...

My modem basically shuts down every day while I'm at work. I try to seed torrents and 7/10 times I come home and the modem is powered on, but no activity on any interfaces. Below is a pic of what I believe you're asking for.

signal.png
 
Your modem signals look fine. What do you mean there's no activity on the interfaces after a reboot? What gets it going again? If your modem reboots then your torrents should pick right back up. If you say you have to power cycle your router then the router is the issue.
 
The modem will just drop everything, like a power cycle except they never come back up. Just stays powered on and never attempts to refresh the signal. It doesn't get going again until i manually unplug the power and plug it back in.

It does power cycle and come back up sometimes, but most days I come home and there is no connection, I have to power cycle it myself to refresh the signal. I feel that it is the device since its the 2nd one with the same issue in 2 geographically different locations.
 
Sorry for necro old thread but this applies to me as well. Please note I'm on barracks wifi as I have no other means for Internet and on my iPad. Comcast been out here twice and Monday is third time.

Here's. what my modem says on page :

Frequency: 487750000
Signal to noise: 23.5 dB
Power level 23.1 dBmV
Upstream

Channel Id:0
Frequency:0 hz
Power 8.3 dBmV


Logs repeat every other line, first line says Qam/qpsk symbol timing
2nd line says Ethernet link up ready to pass packets.

Any ideas at all?

I'm a soldier in the army and really want to talk with friends while on Holiday. (Grew up in foster care--long story.)
 
BlueSage13 said:
Sorry for necro old thread but this applies to me as well. Please note I'm on barracks wifi as I have no other means for Internet and on my iPad. Comcast been out here twice and Monday is third time.

Here's. what my modem says on page :

Frequency: 487750000
Signal to noise: 23.5 dB
Power level 23.1 dBmV
Upstream

Channel Id:0
Frequency:0 hz
Power 8.3 dBmV


Logs repeat every other line, first line says Qam/qpsk symbol timing
2nd line says Ethernet link up ready to pass packets.

Any ideas at all?

I'm a soldier in the army and really want to talk with friends while on Holiday. (Grew up in foster care--long story.)
Click to expand...

If 23dB SNR is the downstream signal levels, you got some major problems there. Should be a minimum of 30dB, preferably around mid 30s. Same with the downstream power level, which should be between -15dBmv and +15dBmv.

Do you have any splitters installed? How is your modem connected? Are all the CATV end connectors attached snuggly?
 
Everything is snug yes. Single splitter on wall to cable about 6 feet of cable ran to modem and a 1 foot cat3.

So anything you can think of?

Thanks, eager to get on Skype lol.
 
BlueSage13 said:
Sorry for necro old thread but this applies to me as well. Please note I'm on barracks wifi as I have no other means for Internet and on my iPad. Comcast been out here twice and Monday is third time.

Here's. what my modem says on page :

Frequency: 487750000
Signal to noise: 23.5 dB
Power level 23.1 dBmV
Upstream

Channel Id:0
Frequency:0 hz
Power 8.3 dBmV


Logs repeat every other line, first line says Qam/qpsk symbol timing
2nd line says Ethernet link up ready to pass packets.

Any ideas at all?

I'm a soldier in the army and really want to talk with friends while on Holiday. (Grew up in foster care--long story.)
Click to expand...

Your signals are out of whack and you'll need a visit from a tech (probably). Can you post a picture of your modem's signal page? I'm having trouble discerning which power level you posted is the upstream and downstream.
 
Ehren8879 said:
Your signals are out of whack and you'll need a visit from a tech (probably). Can you post a picture of your modem's signal page? I'm having trouble discerning which power level you posted is the upstream and downstream.
Click to expand...

Thanks for taking the time. :)

I don't see an option for uploading attachments. I'll see if I can get on Flickr one moment.
 
I just refreshed the page a couple times and I'm getting now:

Rec per level.: -5.7
Signal: 24.7

Much diff then before...still no access. That was after a power cycle.
 
Last update....I don't want to clog the forums with my problem lol... But signal to noise just flatlined at 0.0 and hasn't come back. :-(
 
BlueSage13 said:
Last update....I don't want to clog the forums with my problem lol... But signal to noise just flatlined at 0.0 and hasn't come back. :-(
Click to expand...

That means your modem is offline.

Check your connection for a line amplifier. Your receive power is +18.5 which is way too high and appears to be fluctuating based on your first posting. Transmit power is 8dBmV which further supports my theory that your line might be amped (If you want to know why, I can elaborate later).

If present,that amp can either be removed or needs to be replaced.


If no amp is present than your cable company has a jacked up line extender or trunk amp
 
simple fix for me was: get a new modem. I had spent two weeks trying to track and troubleshoot the issue with my 5101/5201 modems and just got tired loosing access to my home ftp server while I was away. Purchased one of the new Surfboards and haven't had these long disconnects in a while
 
I'm having this issue - everything works until I try and load the connection.

Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 3 117000000 Hz -3.5 dBmV 37.2 dB 2 0

Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked TDMA and ATDMA 4 2560 Ksym/sec 32000000 Hz 37.9 dBmV

My log that I cleared and then ran for a few minutes:
Sun May 05 18:09:50 2013 Notice (6) TLV-11 - unrecognized OID;CM-MAC=3c:75:4a:9d:fd:07;CMTS-MAC=00:30:b8:c1:53:00;CM-QOS=1.1;CM-VER=3.0;
Time Not Established Warning (5) DHCP WARNING - Non-critical field invalid in response ;CM-MAC=3c:75:4a:9d:fd:07;CMTS-MAC=00:30:b8:c1:53:00;CM-QOS=1.0;CM-VER=3.0;
Sun May 05 18:09:08 2013 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=3c:75:4a:9d:fd:07;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
Sun May 05 18:09:06 2013 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=3c:75:4a:9d:fd:07;CMTS-MAC=00:30:b8:c1:53:00;CM-QOS=1.1;CM-VER=3.0;
Sun May 05 18:09:04 2013 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=3c:75:4a:9d:fd:07;CMTS-MAC=00:30:b8:c1:53:00;CM-QOS=1.1;CM-VER=3.0;
Sun May 05 18:08:40 2013 Critical (3) SYNC Timing Synchronization failure - Failed to receive MAC SYNC frame within time-out period;CM-MAC=3c:75:4a:9d:fd:07;CMTS-MAC=00:30:b8:c1:53:00;CM-QOS=1.1;CM-VER=3.0;
Sun May 05 18:05:53 2013 Critical (3) SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=3c:75:4a:9d:fd:07;CMTS-MAC=00:30:b8:c1:53:00;CM-QOS=1.1;CM-VER=3.0;
 
You might be having intermittent noise on your line. Check all your cables and devices. Try disconnecting TVs one at a time and see if the cable modem issue goes away. Try moving the cable modem temporarily to the cable drop as it comes into your home or apartment. If you still have the problem, then it may be an outside plant issue and your cable provider will need to do a truck roll to fix it.
 
I actually only have internet service no TV's as they are on DirectTV. They are coming out today - when I called from work they showed a 22 dBm upstream SNR. Hoefully that fixes it.
 
Last edited:
You must log in or register to reply here.
Back
Top