Openreach DLM speed reduced on the line

I just noticed DLM had resync just after 1:25pm today (very disappointed with massive huge 8701Kbps knocked off from 80000Kbps)

xDSL
Mode VDSL2
Traffic Type PTM
Status Up
Link Power State L0
Downstream Upstream
Line Coding (Trellis) On On
SNR Margin (dB) 6.1 12.1
Attenuation (dB) 11.6 0.0
Output Power (dBm) 12.5 0.0
Attainable Rate (Kbps) 71571 22147
Rate (Kbps) 71299 19999

DSLAM type / SW version: BDCM:0xa48c (164.140) / v0xa48c
Modem/router firmware: AnnexA version - A2pv6F039g1.d24m
DSL mode: VDSL2 Profile 17a
Status: Showtime
Uptime: 2 hours 59 min 22 sec
Resyncs: 1 (since 01 Mar 2019 13:25:45)

Downstream Upstream
Line attenuation (dB): 11.6 0.0
Signal attenuation (dB): Not available on VDSL2
Connection speed (kbps): 71299 19999
SNR margin (dB): 6.1 12.1
Power (dBm): 12.5 0.0
Interleave depth: 16 1
INP: 48.00 0
G.INP: Enabled Not enabled
Vectoring status: 5 (VECT_UNCONFIGURED)

RSCorr/RS (%): 0.0000 0.0000
RSUnCorr/RS (%): 0.0000 0.0000
ES/hour: 0 0

IP Profile has dropped too at 68.93Mbps

Do u think DLM will try lower SNR from 6dB to 3dB next step?

In reply to a post by adslmax:

Do u think DLM will try lower SNR from 6dB to 3dB next step?

Dunno, mine's been around 3dB (currently 3.8) for as long as I can remember.

Rather surprise my line got both interleaved ON after resync around 1:40am today

Downstream Upstream
Line attenuation (dB): 11.5 0.0
Signal attenuation (dB): Not available on VDSL2
Connection speed (kbps): 78451 20000
SNR margin (dB): 6.6 14.1
Power (dBm): 12.4 -0.6
Interleave depth: 8 8
INP: 46.00 47.00
G.INP: Enabled Enabled

Upstream G.INP, that's why.

Hope Downstream SNR will reduced to 3dB sooner or later to get back to 80Mbps.

I wouldn't be surprised if it takes some time to reduce. My own line reduced right down first to ~3dB then ~1.8dB, over the previous 18 months - weirdly both reductions happened in the summer July/Aug time, one year then the next!

A change of ISP last November must have caused a DLM reset and I'm back over 6dB and been there ever since.

DLM never reduces SNRM to 1.8dB. It's lowest setting is 3dB.

Anything below 3dB is due to increased noise since the sync.

My parents line got SNR 3dB for the last 10 months now. Never went below this.

The line has resync this afternoon before 2pm and now back to 80Meg.

Downstream Upstream
Line attenuation (dB): 11.6 0.0
Signal attenuation (dB): Not available on VDSL2
Connection speed (kbps): 80000 19999
SNR margin (dB): 6.3 14.8
Power (dBm): 12.5 0.0
Interleave depth: 8 1
INP: 49.00 0
G.INP: Enabled Not enabled
Vectoring status: 5 (VECT_UNCONFIGURED)

adsl info --pbParams
adsl: ADSL driver and PHY status
Status: Showtime
Last Retrain Reason: 1
Last initialization procedure status: 2
Max: Upstream rate = 28573 Kbps, Downstream rate = 83617 Kbps
Bearer: 0, Upstream rate = 19999 Kbps, Downstream rate = 80000 Kbps
Bearer: 1, Upstream rate = 0 Kbps, Downstream rate = 0 Kbps
Discovery Phase (Initial) Band Plan
US: (7,32) (871,1205) (1972,2782)
DS: (33,859) (1216,1961) (2793,3970)
Medley Phase (Final) Band Plan
US: (7,32) (871,1205) (1972,2782)
DS: (33,859) (1216,1961) (2793,3970)
VDSL Port Details Upstream Downstream
Attainable Net Data Rate: 28573 kbps 83617 kbps
Actual Aggregate Tx Power: 0.0 dBm 12.5 dBm
====================================================================================
VDSL Band Status U0 U1 U2 U3 U4 D1 D2 D3
Line Attenuation(dB): 2.7 13.3 20.5 N/A N/A 6.9 15.8 26.4
Signal Attenuation(dB): 2.7 12.4 19.5 N/A N/A 8.9 15.7 26.4
SNR Margin(dB): 14.5 15.1 14.7 N/A N/A 6.5 6.2 6.0
TX Power(dBm): -14.9 -30.5 -0.1 N/A N/A 8.3 7.8 7.0

Got power cut three days ago (first time we has our power cut for a year)


xDSL
xDSL
Mode VDSL2
Traffic Type PTM
Status Up
Link Power State L0
Downstream Upstream
Line Coding (Trellis) On On
SNR Margin (dB) 9.0 15.3
Attenuation (dB) 11.5 0.0
Output Power (dBm) 12.4 -0.3
Attainable Rate (Kbps) 95323 36358
Rate (Kbps) 79999 19999
B (# of bytes in Mux Data Frame) 130 237
M (# of Mux Data Frames in an RS codeword) 1 1
T (# of Mux Data Frames in an OH sub-frame) 0 42
R (# of redundancy bytes in the RS codeword) 8 16
S (# of data symbols over which the RS code word spans) 0.0518 0.3781
L (# of bits transmitted in each data symbol) 21468 5374
D (interleaver depth) 16 1
I (interleaver block size in bytes) 139 127
N (RS codeword size) 139 254
Delay (msec) 0 0
INP (DMT symbol) 48.00 0.00