Intermittent Network - Drop outs
Intermittent Network - Drop outs
Forum Discussion
36 Replies
I'm looking at the US is this on the high side? I believe these should be around the low 40's ?
It is a Hub 5
Had a very similar thing this week. Just "magically" started one afternoon... and just as mysteriously went away again... ( 2025-07-18 )
( Yesterday evening - 2025-07-21 )
it's been rock solid before. No explanation at all from VM.
This a hub 4 or 5 by the way?
It is a 5, applogies it didn't reply to you directly, I haven't used the new forum until now
"Maximum Number of CPEs 3"
How did you get 3? this normally is 1
I didn't even spot that, would that include the TV box?
If not, seems someone at Virgin has been messing around with the profiles.
I know the router has been replaced twice before so maybe they forgot to remove the bindings on the CMTS.
I wonder what happens if you plug 3 modems in? Never heard of that being done before.
Has anyone ever heard of more than 1 CPE?
Yes the Tivo boxes count as CPEs
3.0 Upstream channels
Channel Frequency (Hz) Power (dBmV) Symbol Rate (ksps) Modulation Channel ID
0 49600000 48.5 5120 QAM 64 1
1 43100000 48.8 5120 QAM 64 2
2 36600000 48.5 5120 QAM 64 3
3 30100000 49 5120 QAM 64 4
4 23600000 49.5 5120 QAM 64 5
3.0 Upstream channelsChannel Channel Type T1 Timeouts T2 Timeouts T3 Timeouts T4 Timeouts
0 ATDMA 0 0 0 0
1 ATDMA 0 0 0 0
2 ATDMA 0 0 0 0
3 ATDMA 0 0 0 0
4 ATDMA 0 0 1 0
3.1 Upstream channelsChannel Channel Width (MHz) Power (dBmV) FFT Type Modulation
6 10.4 43.7 2K QAM 256
3.1 Upstream channelsChannel Channel Type Number of Active Subcarriers First Active Subcarrier (Hz) T3 Timeouts T4 Timeouts
6 OFDMA 208 74000000 0 03.0 Downstream channels
Channel Frequency (Hz) Power (dBmV) SNR (dB) Modulation Channel ID
1 347000000 1.3 38 QAM 256 27
2 139000000 0.6 35 QAM 256 1
3 155000000 0.5 35 QAM 256 3
4 163000000 0.4 35 QAM 256 4
5 171000000 0 35 QAM 256 5
6 179000000 0.2 36 QAM 256 6
7 187000000 0.4 35 QAM 256 7
8 195000000 0.5 35 QAM 256 8
9 203000000 -1 35 QAM 256 9
10 211000000 -1 35 QAM 256 10
11 219000000 -1.4 36 QAM 256 11
12 227000000 -1.5 36 QAM 256 12
13 235000000 -1.2 36 QAM 256 13
14 243000000 0.7 36 QAM 256 14
15 251000000 0.6 36 QAM 256 15
16 259000000 0.4 36 QAM 256 16
17 267000000 0.4 36 QAM 256 17
18 275000000 0.3 36 QAM 256 18
19 283000000 0 36 QAM 256 19
20 291000000 0.3 37 QAM 256 20
21 299000000 0.7 37 QAM 256 21
22 307000000 0.9 37 QAM 256 22
23 315000000 0.9 37 QAM 256 23
24 323000000 1 37 QAM 256 24
25 331000000 1 37 QAM 256 25
26 339000000 1.1 37 QAM 256 26
27 355000000 1.5 38 QAM 256 28
28 363000000 1.7 38 QAM 256 29
29 371000000 1.7 38 QAM 256 30
30 379000000 1.8 38 QAM 256 31
31 387000000 1.8 38 QAM 256 32
3.0 Downstream channelsChannel Locked Status RxMER (dB) Pre RS Errors Post RS Errors
1 Locked 38 0 0
2 Locked 35 1 0
3 Locked 35 4 0
4 Locked 35 0 0
5 Locked 35 0 0
6 Locked 36 0 0
7 Locked 35 0 0
8 Locked 35 0 0
9 Locked 35 0 0
10 Locked 35 0 0
11 Locked 36 0 0
12 Locked 36 0 0
13 Locked 36 0 0
14 Locked 36 0 0
15 Locked 36 0 0
16 Locked 36 0 0
17 Locked 36 0 0
18 Locked 36 0 0
19 Locked 36 0 0
20 Locked 37 0 0
21 Locked 37 0 0
22 Locked 37 0 0
23 Locked 37 0 0
24 Locked 37 0 0
25 Locked 37 0 0
26 Locked 37 0 0
27 Locked 38 0 0
28 Locked 38 0 0
29 Locked 38 0 0
30 Locked 38 0 0
31 Locked 38 0 0
3.1 Downstream channelsChannel Channel Width (MHz) FFT Type Number of Active Subcarriers Modulation (Active Profile) First Active Subcarrier (Hz)
33 94 4K 1840 QAM 4096 1108
3.1 Downstream channelsChannel ID Locked Status RxMER Data (dB) PLC Power (dBmV) Corrected errors (Active Profile) Uncorrectable errors (Active Profile)
33 Locked 0 -2.8 7994036 0Time Priority Description 21-07-2025 15:42:29 notice US profile assignment change. US Chan ID: 6; Previous Profile: 11 13; New Profile: 12 13.;CM-MAC=dc:92:72:56:4b:0d;CMTS-MAC=00:01:5c:97:80:bd;CM-QOS=1.1;CM-VER=3.1; 21-07-2025 15:42:22 notice REGISTRATION COMPLETE - Waiting for Operational status 21-07-2025 15:42:12 notice DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=dc:92:72:56:4b:0d;CMTS-MAC=00:01:5c:97:80:bd;CM-QOS=1.1;CM-VER=3.1; 21-07-2025 15:42:10 warning DHCP WARNING - Non-critical field invalid in response ;CM-MAC=dc:92:72:56:4b:0d;CMTS-MAC=00:01:5c:97:80:bd;CM-QOS=1.1;CM-VER=3.1; 21-07-2025 15:42:08 notice Honoring MDD; IP provisioning mode = IPv4 21-07-2025 15:42:06 critical No Ranging Response received - T3 time-out;CM-MAC=dc:92:72:56:4b:0d;CMTS-MAC=00:01:5c:97:80:bd;CM-QOS=1.1;CM-VER=3.1; 21-07-2025 15:42:01 critical SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=dc:92:72:56:4b:0d;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.1; 21-07-2025 15:42:00 critical Cable Modem Reboot because of - HW or Power-On Reset See above, just note that symptoms don't match the graph, currently on site with Cat 6, ping test and was sitting at 60MS to 8.8.8.8 for some time.
Got it down to a more reasonable 30 but it is extremely jittery.
https://www.thinkbroadband.com/broadband/monitoring/quality/share/baacaa7912823a3d028fcae76b6fb781e71bf154
Hi, I’ve been dealing with a very similar issue; frequent dropouts, high latency, and DOCSIS 3.1 upstream not locking (falling back to 3.0). My BQM shows periods of instability, and the Hub 5 logs are filled with ranging failures (T3/T4 timeouts).
Virgin Media support initially focused on internal wiring and equipment replacement, but the real issue appears to be upstream - possibly signal levels or provisioning at the cabinet or CMTS.
Would be interested to see if you’re seeing similar log entries or BQM results.
