Kitz Forum

Broadband Related => Telephony Wiring + Equipment => Topic started by: sheddyian on August 21, 2018, 10:13:05 PM

Title: Intermittent noisy line
Post by: sheddyian on August 21, 2018, 10:13:05 PM
For the past 10 days or so I've had an intermittent noisy line.  Mostly it's crackles, but often there's a hum as well.  Also to be heard are fizzes and the occasional firework-style "wheeeeee" noise.

Twice I've tried to report it to Plusnet, the first time the noise went away completely and the test instigated by the call-handler came back clear.  2nd time (this morning) it was crackling away merrily, I waited 10 minutes or so in a queue and by which time the noise had all but gone.  The operator did comment on a slight crackle he heard, but the test came back clear once more.     >:(

I'd already plugged a wired handset into the test socket, and heard crackles and noise.  I did this again today for the call handler, and when I later tried to unplug the phone from the test socket, it bent one of the pins on the recently installed Master Socket 5C  :o

I happened to have a spare, so quickly replaced it, optimistically wondering if this would clear the crackly line, but it did not.

Plusnet are calling me back tomorrow to see how it's going, mostly I'm waiting for it to be especially noisy and hoping I can get through to them straight away such that a line test can be performed when there's noise present.

Meanwhile, does anyone have any thoughts as to what the cause is likely to be, and if there's anything else I might do? 

It seemed worse after it had been raining hard, although it's been dry for a few days now and it's still noisy.  It possibly improves the more the line is used for voice calls.  It doesn't seem to have affected my broadband connection, which has remained steady with a few errors here and there.  But the noise is intermittent and isn't always there.

Thanks

Ian
Title: Re: Intermittent noisy line
Post by: burakkucat on August 21, 2018, 10:29:28 PM
For the past 10 days or so I've had an intermittent noisy line.  Mostly it's crackles, but often there's a hum as well.  Also to be heard are fizzes and the occasional firework-style "wheeeeee" noise.

Would that be like 50 Hz mains hum?

Quote
. . . and when I later tried to unplug the phone from the test socket, it bent one of the pins on the recently installed Master Socket 5C  :o

They are a really horrible construction, built to a cost and not to a specification.  :-X

I suspect a faulty joint will be responsible for the crackling and an intermittent earth contact fault would account for the (mains) hum.
Title: Re: Intermittent noisy line
Post by: sheddyian on August 21, 2018, 10:41:42 PM
Would that be like 50 Hz mains hum?

It's down that end of frequency, yes.  It's sometimes a bit of an echoey hum.  The person I'm talking to can't hear a hum, but has noticed a fizzing sound (which I don't tend to hear).

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  (NTE5C)They are a really horrible construction, built to a cost and not to a specification.  :-X

I've got a MK4 VDSL plugged into it and it doesn't seem to be a very positive connection.  The silver contacts on the top of the plug on this are already looking discoloured!

This was the first thing I fiddled with when the crackling started.
[/quote]

Quote
I suspect a faulty joint will be responsible for the crackling and an intermittent earth contact fault would account for the (mains) hum.

I will be interested to learn myself, if I'm told  :D 

This line has always been a bit quiet for voice calls, though it passed tests when the engineer fitted the new socket and has yet to fail at any tests except the "using it and making phone calls without line noise" test  ::)

Ian
Title: Re: Intermittent noisy line
Post by: burakkucat on August 21, 2018, 11:24:00 PM
It's down that end of frequency, yes.  It's sometimes a bit of an echoey hum.  The person I'm talking to can't hear a hum, but has noticed a fizzing sound (which I don't tend to hear).

I would be willing to stake a box of kitteh-treats on the fault being a joint beginning to show HR or semi-conductive tendencies, coupled with water penetration into the joint closure providing a conductive path to earth.

Quote
I've got a MK4 VDSL plugged into it and it doesn't seem to be a very positive connection.  The silver contacts on the top of the plug on this are already looking discoloured!

I would probably replace both items with an NTE5/A and a Mk 3 SSFP pairing.  ;)

[Edited to fix a spelling mishap.]
Title: Re: Intermittent noisy line
Post by: 4candles on August 22, 2018, 03:35:32 PM
I second Mr Cat on both points.


Mk3s seem to hard to find now - I suppose Openreach regard them as obsolescent with the introduction of the 5C & Mk4.   :(
Title: Re: Intermittent noisy line
Post by: sheddyian on August 30, 2018, 10:32:53 AM
Thanks for the replies.  Annoyingly, the intermittent fault has gone away, and the line is free from crackles and pops and hums at the moment.  So I couldn't get it looked at as it kept passing the line test.

My attainable line speed has been gradually dropping though, originally around 45,000 now nearer 42,000.  (Since my package is a 40mb one, this doesn't affect me as such, but it's indicative.  Of something  ???  )

Ian
Title: Re: Intermittent noisy line
Post by: sheddyian on December 19, 2018, 10:13:30 AM
Some time passes...

The crackles come and go, but I don't use the line much and it isn't impacting the DSL, so I largely ignored it.

Recently it got a lot worse - constant noise.  So I logged a call with Plusnet last week, and today an Openreach engineer came around. 

First thing I did this morning was pick up the phone, and it was buzzing quite loudly with occasional crackles.  An hour later when the engineer arrived, of course the fault had gone away.

But he believed me, and plugged his test equipment into the socket.  It showed a slight fault early on, and failed a later test.  He wondered if the socket was at fault, and so took it off the wall and tested the pair from the dropwire.

This passed the tests, so he fitted a new socket.

So far, it's all working fine.   :fingers:

Curiously, annoyingly... if you read the start of this thread, you'll see that the crackling has been there for some months, and early on during diagnostics, I'd damaged the socket and so had replaced it.  Therefore the original socket was showing a fault, and the one I'd replaced it with showed the same fault. 

I am thus hoping that I'd replicated the original fault in my repair - the alternative is that the intermittent fault has just gone quiet for a bit and will come back in due course.

Also disappointingly, the DSL stats are pretty much the same as before - I was imagining a line fault under the road somewhere that would miraculously give me extra bandwidth when repaired  :D

Still, if it's all fixed, I'm happy

Ian