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Sanity Check - (I have intermittant hiss on the line & poor speeds)

xpcomputers
Grafter
Posts: 460
Registered: 13-04-2007

Sanity Check - (I have intermittant hiss on the line & poor speeds)

Hi Guys,
So I wanted to run a sanity check on what I am seeing, and what I should do about it. Make sure I'm not missing the obvious etc etc.
I think better when talking things through with others out loud.... so will you be my sounding board?
My speeds have plummeted....

BT Speed tester tonight:

Quote
Download speed achieved during the test was - 442 Kbps
For your connection, the acceptable range of speeds is 50-500 Kbps.
Additional Information:
Your DSL Connection Rate :4352 Kbps(DOWN-STREAM), 448 Kbps(UP-STREAM)
IP Profile for your line is - 500 Kbps

My router stats at a bad point::
Quote
2010-05-06 16:05
Connected true
Operational Mode G.Dmt
Annex Type ADSL2M
Upstream 448000
Downstream 640000
CO Vendor TSTC
Elapsed Time 7 day 5 hr 2 min 31 sec
Downstream Upstream
SNR Margin 32.5 dB 19 dB
Line Attenuation 44.0 dB 24.5 dB
CRC Errors 2 22
Latency Interleave Interleave


Then after a recent reboot:
Quote
2010-05-08 00:07
Connected true
Operational Mode G.Dmt
Annex Type ADSL2M
Upstream 448000
Downstream 4352000
CO Vendor TSTC
Elapsed Time 0 day 1 hr 52 min 38 sec
ADSL
Parameters
Downstream Upstream
SNR Margin 10.5 dB 21 dB
Line Attenuation 43.5 dB 24.5 dB
CRC Errors 2 0
Latency Interleave Interleave

I get intermittent hiss and crackles on the phone line.
I've been trying to catch the hisses in action to run tests from the test socket on the NTE5, but never manage to catch them in action from there. (But then even hanging up the phone and making a fresh call often clears it, if not on the first time, it does on the second - I think I read this is common since the "flashing" the phone hook like that can cause bad connection points on the line to improve temporarily? Is that true?). I've caught the hisses on the "quiet line test" a few times, but never managed to yet catch them from the test socket... but not managed to prove anything decisively  from that either, since the line is always still clean sounding when faceplate put back on too.
Problem is I can't run the router from the test socket permanently, since it is in my son's bedroom, and being 20months old is fascinated by wires & buttons! (But can run any tests from there for a limited time at any point as long as he's entertained elsewhere)
Accordingly I have the Clarity modified BT faceplate to run the ADSL signal hardwired off the A & B terminals on the rear of the faceplate, which runs the ADSL signal 1m (in CAT5e cable) through the wall to a cat5e socket for the router. The house phone sockets then come off the 2, 3 & 5 terminals on the rear of the faceplate and are therefore pre-filtered by the faceplate, so have no plug-in filters installed. I was told by Clarity that A & B to a Cat5e socket was the correct way to install this (eg no filter on the ADSL signal between A & B and the router), which concerns me slightly, but the only way to test this with a filter would be to disconnect the wiring of the cat5e and run it through a BT socket so I can filter the signal and pull the router off the ADSL side of a plug in filter.
Am I right to question Clarity's advice about not needing a filter on the A & B pair feeding the router? My logic tells me it DOES need one, but it currently doesn't have one fitted since it would fit without rewiring. (BUT I don't want to be faffing with rewiring things if not needed, since I've been permanently shattered lately, (and my 2nd child is due to be born any day!) - but if it is worth a go, then I'll tackle it at some point since the speed problem is a serious drag).
Long story cut slightly shorter than I could easily babble on for (sorry for length already):-
..... given the constraints of not being able to run the router from the test socket 24/7, what would you do next to work out if the problem is with me or BT?
Need any more info, then ask.... and won't be offended by any questions or suggestions no matter how basic... since I could well have missed the obvious!!!
Am I missing anything else before I report it to Plusnet?
Thanks everyone....
Mike
ps... Oh and despite paying for it, I've never had caller display  working at this house (been here a year), and keep meaning to troubleshoot that too, since it could be caused by a related problem!
pps... router is Billion 7404VGO(M) if that makes a difference, and I prefer to use it since it handles my VOIP phone line to a proper phone.
ppps... if it makes a difference, I want to upgrade onto a Pro account and an ADSL2+ connection ASAP too, but thought it prudent to chase the fault first... however if the ADSL2+ shift might solve it itself, then happy to take the plunge (since it can't make things much worse surely and at least I'd be re-terminated at the exchange so know that isn't the problem if I still have the fault afterwards!). If that sounds like a good test to others, then I'll order the upgrade and see.
5 REPLIES
Superuser
Superuser
Posts: 9,149
Thanks: 551
Fixes: 46
Registered: 06-04-2007

Re: Sanity Check - (I have intermittant hiss on the line & poor speeds)

My understanding is that plug-in filters pass the line signal untouched to the ADSL socket on the filter, just filter the phone socket to remove incoming and outgoing signals at broadband frequencies. I think that confirms Clarity's advice that no filter is needed on the A/B signal from their faceplate (as long as it feeds only a router).
Quote from: xpcomputers
My router stats at a bad point::
Quote
Upstream 448000
Downstream 640000
CO Vendor TSTC
Elapsed Time 7 day 5 hr 2 min 31 sec
Downstream Upstream
SNR Margin 32.5 dB 19 dB
Line Attenuation 44.0 dB 24.5 dB

To me that suggests noise on your line (7 days ago) caused the router to lose sync, regaining it at just 640kbps. Since then the noise had gone away, and the SNR Margin increased as a result to 32.5dB because the low sync speed remained in effect. Had you re-synced at that point the sync speed would have increased again reducing the SNRM to its target value.
Quote from: xpcomputers
Then after a recent reboot:
Quote
Upstream 448000
Downstream 4352000
CO Vendor TSTC
Elapsed Time 0 day 1 hr 52 min 38 sec
Downstream Upstream
SNR Margin 10.5 dB 21 dB
Line Attenuation 43.5 dB 24.5 dB

Then 2 hours before your post you did re-sync and sync speed increased to 4352kbps, but the BT speedtest shows your IP profile had yet to increase from the value of 500kbps corresponding to syncing at 640kbps. That might well have increased now to 3500kbps since the change is huge.
Quote from: xpcomputers
I get intermittent hiss and crackles on the phone line.
I've been trying to catch the hisses in action to run tests from the test socket on the NTE5, but never manage to catch them in action from there. (But then even hanging up the phone and making a fresh call often clears it, if not on the first time, it does on the second - I think I read this is common since the "flashing" the phone hook like that can cause bad connection points on the line to improve temporarily? Is that true?). I've caught the hisses on the "quiet line test" a few times, but never managed to yet catch them from the test socket... but not managed to prove anything decisively  from that either, since the line is always still clean sounding when faceplate put back on too.

I think those paragraphs are the key to fixing this. It looks like a phone fault, and from the behaviour/symptoms described I would guess it is almost certainly external to your premises even though you haven't been able to confirm that from the test socket (but note that is a layman's opinion - I'm not a telecommunications expert).
Even though you can't file a 'noisy line' fault with your phone provider with the noise ongoing I would think it is worth raising this problem (as a phone fault) with them - 'sometimes making conversation impossible'. Hopefully they'll get an Openreach engineer to check out the line. They might, at least, try a different pair between you and the street cabinet.
My opinion for what it's worth.
David
David
gwowders
Grafter
Posts: 70
Registered: 05-10-2009

Re: Sanity Check - (I have intermittant hiss on the line & poor speeds)

Quote from: xpcomputers
I get intermittent hiss and crackles on the phone line.
I've been trying to catch the hisses in action to run tests from the test socket on the NTE5, but never manage to catch them in action from there. (But then even hanging up the phone and making a fresh call often clears it, if not on the first time, it does on the second - I think I read this is common since the "flashing" the phone hook like that can cause bad connection points on the line to improve temporarily? Is that true?). I've caught the hisses on the "quiet line test" a few times, but never managed to yet catch them from the test socket... but not managed to prove anything decisively  from that either, since the line is always still clean sounding when faceplate put back on too.

I've got a similar story but with a much simpler setup than yourself.  I have managed to catch the *hiss and crackle* on the line from the master socket BUT it only happens when my modem is plugged in and tries to sync - I have tried several filters and am convinced its not that.  A stright forward phone connected up to the master socket doesn't display the same characteristics.
It is intermittent - which drives me bonkers!!!!
xpcomputers
Grafter
Posts: 460
Registered: 13-04-2007

Re: Sanity Check - (I have intermittant hiss on the line & poor speeds)

Thanks guys.
I had a VERY noisy phone call with someone this morning which lead me to investigate a bit. Whilst still on the call I tried unplugging the router's RJ11 lead from the wall, and the noise dropped off tremendously suggesting that the router might be at fault... except that the line was still noisy and crackling without the router connected at all... just much more bearable so we could then hear each other.
So I suspect that the router itself is probably fine and the fault lies elsewhere, but it ramps up the gain to shout over the noisy line which makes things worse. Is that feasible? Not ruling out a faulty router though just yet... but looking less likely. Will try to run a series of tests with a Plusnet supplied router too, but tricky since I lose the VOIP for the tests, and the problem is intermittent!!
Yet the quiet line test displayed noise, but not from the master socket.... but then neither did any other sockets sound noisy after that either. Again it would seem a serious of hook flashes clears it, so each quiet line test is quieter than the last! (until next time!). I guess it could be dampness induced (or dampness drying out apparently!) or anything like that....
I also did some research too to check the "clarity" claims, and everyone seems to agree with them and you, unless I have a faulty faceplate, then my wiring seems less likely to be the problem. I might get myself a ADSL nation faceplate to swap in, which would help me prove the Clarity one isn't faulty.
Just to be sure, I'm about to crimp a RJ11 plug onto a spare dongle filter, so I can filter the feed from the RJ45 socket that goes to the router.
When I moved in to the house year ago, the previous owner had had NTL/Virgin Cable for many years, so the BT master socket looked old and rusty. They needed to swap the pairs then to even get me working at all, so that might suggest that a whole run of cable is on it's last legs... unfortunately I don't know enough about what they actually swapped then which might have been useful info for talking to a BT guy about. I had to fight them to change the Master socket then too... since the guy said it was fine!!! (we are talking rusty terminals everywhere inside it!). In the end, I asked the guy if he'd like that master socket in his own house... and he then changed it instantly!!!!  Grin  Cool
No closer really.... yet. I think I will try to tally the line noise with the rain patterns to see if it appears to be weather related.
Thanks again,
Mike
xpcomputers
Grafter
Posts: 460
Registered: 13-04-2007

Re: Sanity Check - (I have intermittant hiss on the line & poor speeds)

I've logged this with the fault checker and we'll see where we get to.
Ticket: 33296582
I managed to make an RJ11 filter dongle, and connected it up for the router. Seemingly no change, so probably making no difference. Trouble is being there with the phone off the hook when the crackles & hisses come is tricky since they are intermittent!!!
Mike
Plusnet Alumni (retired) orbrey
Plusnet Alumni (retired)
Posts: 10,540
Registered: 18-07-2007

Re: Sanity Check - (I have intermittant hiss on the line & poor speeds)

Hi Mike,
I've just had a quick look at the ticket and it seems everything is in hand - please let us know if things get worse and I'll give it a kick for you.