cancel
Showing results for 
Search instead for 
Did you mean: 

Frequent T3 timeouts and internet dropping

wardy277
Joining in

I have been getting this issue on and off for the past 6 months. The modem is reporting lots of T3 timeouts causing the internet to drop for a few minutes. This seems to be happening at random times, and is getting more frequent

I have the Hub5 setup in modem mode. This is the second one as VM replaced the first as a precaution. I have setup a ping sensor in homeassistant to help be log when these occur:

27 March 2024
    7:00:59 am
    7:58:58 am
    13:17:03 am
26 March 2024
   11:16:09 am
22 March 2024
    2:17:24 am
19 March 2024
    10:21:47 pm
    1:07:33 pm

I have had an engineer out who tested everything and couldn't find the issue. Replaced the modem and filter, but i am still getting the issues. I have been in touch with VM support via watsapp which seem to be clueless and refuse to send out an engineer. Twice now i have been told that they will monitor, but not hear back from them

The worst response i got was today:

 

 

Thank you so much for sharing all the information. The hubs that are offered to our customers are the regular one's which are suitable for residential usage purpose only, these lags or issue with the internet connection are possible sometimes and we suggest our customers to reboot or reset the hub the hub at those times.

 

 

They seem to imply this is fine for residential and tried to sell me on a support package. I have rebooted and reset the hub multiple times, which sort of solves the issue, but not for long. Mostly it happens in the middle of the night, but has become more frequent and now during the day, which isnt ideal as both me and the wife work from home

All I want is a stable internet connection, is that so hard to ask for? I am in Saltash, Area Ref :18

 

 

27-03-2024 13:20:31	critical	Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
27-03-2024 13:20:31	critical	16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
27-03-2024 13:20:07	critical	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
27-03-2024 13:19:57	critical	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
27-03-2024 13:19:57	critical	Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
27-03-2024 13:19:57	critical	16 consecutive T3 timeouts while trying to range on upstream channel 0;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
27-03-2024 13:19:46	critical	Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
27-03-2024 13:19:46	critical	16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
27-03-2024 13:18:59	critical	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
27-03-2024 13:18:58	critical	Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
27-03-2024 13:18:58	critical	16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;
27-03-2024 13:18:55	critical	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=**:**:**:**:**:**;CMTS-MAC=**:**:**:**:**:**;CM-QOS=1.1;CM-VER=3.1;

 

 

The modems Status:

Cable Modem StatusItem Status TypeChannel Overview Downstream Upstream

Cable Modem StatusOnlineDOCSIS 3.0
Primary downstream channelLockedSC-QAM
DOCSIS 3.0 channels315
DOCSIS 3.1 channels11

 

3.0 Downstream channels

Channel Frequency (Hz) Power (dBmV) SNR (dB) Modulation Channel ID
15390000008.440QAM 25617
24110000007.941QAM 2561
34190000007.840QAM 2562
44270000007.840QAM 2563
54350000007.840QAM 2564
64430000007.740QAM 2565
74510000007.740QAM 2566
84590000007.840QAM 2567
9467000000840QAM 2568
104750000008.340QAM 2569
114830000008.341QAM 25610
124910000008.340QAM 25611
134990000008.340QAM 25612
145070000008.440QAM 25613
155150000008.540QAM 25614
165230000008.440QAM 25615
175310000008.540QAM 25616
185470000008.540QAM 25618
195550000008.640QAM 25619
205630000008.740QAM 25620
215710000008.840QAM 25621
225790000008.941QAM 25622
235870000008.940QAM 25623
245950000008.940QAM 25624
256030000008.840QAM 25625
266110000008.941QAM 25626
27619000000940QAM 25627
286270000008.941QAM 25628
296350000008.940QAM 25629
306430000008.940QAM 25630
31651000000940QAM 25631

3.0 Downstream channels

Channel Locked Status RxMER (dB) Pre RS Errors Post RS Errors
1Locked4025836316
2Locked4114163671
3Locked4016205016
4Locked4030359916
5Locked4030448083
6Locked4018195626
7Locked4021607071
8Locked4029579616
9Locked4028558671
10Locked4021686756
11Locked4126298643
12Locked4025817038
13Locked4030067971
14Locked4029428393
15Locked4031147510
16Locked4026156125
17Locked4026615909
18Locked4028627732
19Locked4016694255
20Locked4021085591
21Locked4024856545
22Locked4124896385
23Locked4027836121
24Locked4027685837
25Locked4025965024
26Locked4128456386
27Locked4022273868
28Locked4122984751
29Locked4023644584
30Locked4026164676
31Locked4025855813

3.1 Downstream channels

Channel Channel Width (MHz) FFT Type Number of Active Subcarriers Modulation (Active Profile) First Active Subcarrier (Hz)
33944K1840QAM 40961108

3.1 Downstream channels

Channel ID Locked Status RxMER Data (dB) PLC Power (dBmV) Corrected errors (Active Profile) Uncorrectable errors (Active Profile)
33Locked419.730402166014
 

3.0 Upstream channels

Channel Frequency (Hz) Power (dBmV) Symbol Rate (ksps) Modulation Channel ID
04960000046.85120QAM 645
14310000046.55120QAM 646
23660000046.55120QAM 647
33010000046.55120QAM 648
42360000046.55120QAM 6410

3.0 Upstream channels

Channel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts
0ATDMA00910
1ATDMA00940
2ATDMA001160
3ATDMA001440
4ATDMA001620

3.1 Upstream channels

Channel Channel Width (MHz) Power (dBmV) FFT Type Modulation
1110.441.52KQAM 256

3.1 Upstream channels

Channel Channel Type Number of Active Subcarriers First Active Subcarrier (Hz) T3 Timeouts T4 Timeouts
11OFDMA208740000001611
 

 

 

 

 

1 REPLY 1

jbrennand
Very Insightful Person
Very Insightful Person

Can you start from a clean sheet and do this....

Switch the Hub off and unplug it from the mains supply for five minutes. Whilst it's off, do a quick check that all of your coax and ethernet cable connections are in nice and "finger" tight - at the Hub and wall box and also at any connectors etc. Ensure there are no “unterminated cable loose ends. Disconnect all the connections and reconnect to be sure. Also check that the internal wiring is ok with no kinking or chaffing. When its light, check that all looks good with the outside cabling and wall box (no “staples, etc.,) piercing the cables.

Then switch the Hub back on and leave ~5 minutes When all done, check back in the settings and ensure that the RS error counts and T3 errors have all reset to 0. Then check every hour or so to see if they start reappearing - they shouldn't. If they do (particularly the postRS and T3 ones) you have a problem (noise) that only a Tech visit will sort. Also check the Upstream QAM’s are all at 64

Also, If you haven’t already, set up a free, secure and “offlsite” - “Broadband Quality Monitor” to continually monitor the state of your connection and record any true network dropouts , latency issues, packet drops, etc - it will thus allow you to differentiate between those and simple wifi dropouts. It does it 24/7/365 and it keeps a visual record of any/all of your network disconnections, useful data to have to match to the Network logs (in your Hub settings) and also in discussions with VM - note it will take a few hours to start seeing a sensible picture - post up the “link” to the “share live graph”. Click the lower link (Share Live Graph) then, click generate. Copy the text in the Direct Link box, beware, there may be more text than you can see. On here click the Link icon (2 links chain to the left of the camera icon) In the URL box paste the link you copied and then click OK
https://www.thinkbroadband.com/broadband/monitoring/quality


--------------------
John
--------------------

I do not work for VM. My services: HD TV on VIP (+ Sky Sports & Movies & BT sport), x3 V6 boxes (1 wired, 2 on WiFi) Hub5 in modem mode with Apple Airport Extreme Router +2 Airport Express's & TP-Link Archer C64 WAP. On Volt 350Mbps, Talk Anytime Phone, x2 Mobile SIM only iPhones.