In reply to a post by retracor:

The DLM on VDSL is meant to be switched off after the first 10 Days.

No, DLM is turned off for the first 2 days and then it's switched on.

Not even that . (My bold and underline):-

2.2.1 Dynamic Line Management
Dynamic Line Management (DLM) is employed in GEA-FTTC. DLM constantly manages lines to maintain a target link quality (speed and stability). It does this for as long as the product exists.

At provision, the line is put on �wide open� VDSL2 line profiles allowing the upstream and downstream line speeds to run at the upper limit of the product option selected.

On the first day of operation, DLM will intervene if severe instability is detected. Otherwise, DLM will wait until the day after provision before deciding if it must intervene, provided that the line has been trained up for at least 15 minutes during the preceding day.

Which in practice means it will leave it alone, or during the night at the end of the second day, when it may add interleaving, and/or G.INP, and/or in serious cases Banding. Changing its mind perhaps at some time in the future.

Edited by RobertoS (Sat 21-Jan-17 15:29:41)

The garage was just an example, many things can create RF that kills ADSL/VDSL2

As for not explaining the ADSL speed issue, actually it could, i.e. noise may follow a pattern (and that's the clue if you find a pattern to drop-outs that its from a source, rather than a wiring fault) of high burst followed by a smaller burst that is not so bad and modem will resync to some extent (this scenario is why banding exists)

The 10-day period is a BT Wholesale myth, despite them continuing to go on about it. Particularly in relation to fibre connections.

See this page for more about it on BT Wholesale ADSLx. On Openreach FTTC the main thing it does is set the IP Profile, instantaneously on every change of connection speed. It may also record the lowest sync during the first 10 days as it did on ADSLx, but that's it.

As William said, correctly in a way but dodgy in the detail, DLM is likely to do nothing for the first two days. He was wrong only in thinking it wasn't running at all and would never do anything in that period.

As BatBoy advised, ideally you should run a diagnostic graphing program 24/7. Of the kit you listed I don't think any allow that except perhaps the Fritz box. Are you on Windows or an Apple machine?

just checked my TP-link router (not PN homehub) and it is showing:

I trust that should put some light on the situation.
Line Status: connected

upload errors of 4294967156
download errors 97

Normal upload speed 1,9 approx. on 40/2 VDSL
current upload approx.0.75
Told by PN the upload should always be 2Mbps.

DSL Modulation Type: VDSL2
Annex Type: Annex A/B/L/M

=================Upstream___Downstream

Current Rate(kbps)_____885______39998
Max Rate(kbps)________897_____ 55142 Max for upload should always be 2000 on 40/2

SNR Margin(dB)-------------10.7------12.6

Line Attenuation(dB)------31.1-------21.7

Errors(pkts)-----------4294967156-----97

Edited by deleted (Sat 21-Jan-17 18:07:23)

You can probably ignore the upstream error figure and just watch for it changing - it is a common bug when a twos complement number is incorrectly displayed ...


Your 4294967156 is very similar to my 4294967290

While similar it is far enough away to suggest a fair few errors and the upload sync so low when getting a full 39998 sync suggests something wrong. Exactly what I don't know.

Probably not the micro filter, as that would also be impacting the downstream, as the bands start Down, Up Down Up Down Up (if brain recalls correctly)

If any HomePlugs in the home or a neighbour who shares an adjoining wall try turning them off and unplugging them (its rare but sometimes people do get issues, since they share a common set of frequencies)

Also does using the test socket make any difference, i.e. no phones connected and none of the extensions are working i.e. proves the test socket is just that and no odd star wiring going on

In reply to a post by MrSaffron:

Probably not the micro filter, as that would also be impacting the downstream, as the bands start Down, Up Down Up Down Up (if brain recalls correctly)

Up0 is te first band up to tone 32 with Down starting at tone 33 ...


from my modem:
Medley Phase (Final) Band Plan
US: (7,32) (871,1205) (1972,2782)
DS: (33,859) (1216,1961) (2793,3970)

Poor brain got it wrong way around then - so raises a chance something in the low frequency band causing problems.

An unfiltered device phone/fax/sky box or failing microfilter can sometimes do this

Thanks to you all for your help and guidance

No power plugs next door I would be surprised if he knew what there were. Not a filter problem as OR already thought that and changed the master socket for a separate modem and telephone type so no filters required on any telephone etc.

the router has lost sync two or three times in the last 12 hours or so needing a reset to sync at the true speed. Had to retype this as it happened during composition of this post.

My neighbour on the other side (not attached to this property) is also on PN but has ADSL.Is it possible that some sort of cross fed would confuse my VDSL and make it try to sync to ADSL.