Help! Why has my connection gone from hero to zero?

[emvisi]

Hi folks

I've been a very happy IDNetter for about 16 months on Home PAYG, but my connection has bombed in the last couple of weeks and I feel like I'm chasing my tail trying to get things working again.

I came back from holiday to discover my IP profile had collapsed down to 135kbps, and an email exchange with IDNet support established that, according to BT, there had been some line instability. Anyway, BT reset my profile and things were back to normal for a couple of days (IP profile up to 5000kbps, d/s line attenuation 42dB, syncing at 4-6000kbps) but I started losing sync again and the profile is back down to 135kbps.

I'd love to know what's gone wrong: the connection has been pretty reliable for so long. I already have a replacement faceplate on the MJU (about 3.5 years old, from clarity.it), the bell wire on the lone extension was disconnected a long time ago, there are additional filters on the two phones and I'm using a shielded modem cable (Belkin I think). Since these problems have arisen, I've completely disconnected the phone extension, I've run everything directly from the test socket, I've moved the router away from anything else electrical, I've walked along the line with a detuned AM radio (there are no sources of electrical interference that haven't existed for the last 15 months) -- and I'm none the wiser. I tried the quiet line test with just the phone plugged into the test socket and it's very clear, albeit with a little crackle every once in a while. Wouldn't even notice it during a conversation.

It's possible that the router (DG834G v2) or all of the filters have failed. However, I don't have spares sitting around so it's going to cost money to confirm this, and even more to get BT off their backsides to do anything. By the way, we're in Virgin Media territory here so I don't know anyone with a DSL modem I can borrow -- all my friends are using cable modems (I ditched mine a few years ago, when it was NTL; it was godawful at the time but it's looking more attractive again by the day...)

Anyway, before I start throwing good money after bad, I'd be very grateful for some guidance as to what I can do to isolate the problem and -- hopefully get back a broadband service worthy of the name.

Thanks,
Mike

[Simon]

Hi Mike,   

I'm not the best person to offer advice (they will come along later), but it does seem as though you've done everything to eliminate a problem within your home wiring (aside from exchanging the router), which would indicate a problem between the BT exchange and your house, although, you didn't mention if you have tried different microfilters in the test socket, and that might be worthwhile, as they can suddenly develop faults. 

IDNet could probably loan you a router, and I think that's possibly the next step you should take, as you need to eliminate all likelihood of the issue being your side of the test socket, to avert the risk of a £160+ call out charge from BT, if they have to investigate.  Of course, the 'little crackle' on the quiet line test may well be a bigger one, when you're not listening, and may be causing the profile drops, but intermittent faults are hellish to prove to BT. 

Hold on for someone more qualified than me to verify this, though. 

Oh, are you on Max or ADSL2+?

[emvisi]

Hi Simon

Thanks for the reply and the Karma 

Apart from the one in the faceplate I have a couple of other filters, which I tried in the test socket (and even daisy-chained them all together) but no difference. One of the filters came with the router and I've no idea where the other one came from. Probably not top-drawer items, but the router is losing sync even when there's nothing happening on the voice circuit.

I'm currently on Max but I have an open order for ADSL2+, due for completion at the end of the week. Great timing!

[Simon]

Ouch, that's certainly not good timing.  ADSL2+ has not been without it's teething problems.  On some lines it, performs worse than Max, and once you switch, there's no going back.

I don't want to worry you unduly, though, so hold fire until one of our more techie people come along.  If not tonight, it will be in the morning. 

[Lance]

Simon is quote correct in what he has posted. Support do have a router they can loan out which would be one way to eliminate or confirm yours. Alternatively, has a friend or family member got a router and some filters you could borrow?

[emvisi]

@Simon
Yes, so I gather 

@Lance
I'll probably get hold of some new filters anyway, but borrowing a modem's a bit tricky -- mostly cable modems around here. I've left a couple of messages, though. Might have some luck tomorrow.

[Sebby]

As others have mentioned, I think it's worth trying another router, as it's certainly a possible cause. Given your setup, it can only really be the router or an external line issue. Try the router, and if it's no good, your only option is going to be to have an engineer out.

[D-Dan]

For the price of return postage - I can lend you one?

Steve

[Ray]

 

[Rik]

Welcome to the Nettery, Em.

I'd echo what everyone else has said, you need to eliminate your router from the equation. If you can post the router's stats (downstream sync speed, noise margin and attenuation) we can have a better stab at what may have been happening, but to get the 135 profile, you have to have had at least one sync event at <288k.

Whereabouts are you, and is your line overhead or underground?

[emvisi]

@Steve
Thanks, that's very kind -- I might well take you up on your offer. Just waiting to find out if one's already on its way.

@Ray
Thanks!

@Rik
I'm in Brighton (Kemptown exchange), and the line comes in to the house from overhead. Router is currently showing:

    Connection speed: 3968kbps
    Line attenuation: 42dB
    Noise margin: 10dB

looks pretty reasonable, and the line's been up for almost 13 hours!!!

Just did a BT speedtest and am very surprised to learn:

    Your DSL connection rate: 3968 kbps(DOWN-STREAM),  448 kbps(UP-STREAM)
    IP profile for your line is - 3000 kbps
    Actual IP throughput achieved during the test was - 2777 kbps

This means the IP profile appears to have been bumped back up overnight, rather than taking several days. Perhaps someone is taking an interest

Now, I'm quite happy with this sort of performance (although I have no objection if it improves). Let's see if it bombs again today...

Mike

[Rik]

Hi Mike

On a 42db line I'd expect you to get another 1-1.5Mb, so that suggests your line is quite noisy. It looks like BT have raised your noise margin to 9 or 12db. If it's 9, then your line is currently less noisy than when you last re-synced, if it's 12, then you have noise around still. The profile is correct for the sync speed, so my guess is that you've had a quick 'bounce' due to the large improvement in sync speed.

We now need to try and work out what happened. Ideally, try with a spare router, IDNet will usually lend one in this sort of situation. In the meantime, do you have, or can you borrow, a battery-powered AM radio? If so, de-tune it from any station so that all you have is white noise. Then, follow the path of your phone line from where it enters the house through to the router. Listen for any increase in the noise level - if you hear one, or more, then your router is also hearing that noise.

[emvisi]

I've managed to locate a spare modem/router, which should be with me tomorrow. It's a noticeably cooler day today, so it'll be interesting to see whether things behave in the meantime.

I tried the radio thing the other day. What I did notice was the noise being kicked out by the radio teleswitch next to the electricity meter, which is about 2ft above where the MJU is located and where the router itself was. However, it's been like that for a good couple of years. Nothing new, and barely discernible using the radio right next to the router itself. In any case, I moved the router well away yesterday on a longer, shielded modem cable, just to see if it made any difference to stability... perhaps it did, although the MJU is still there, under the teleswitch so any lines in or out would still be susceptible to its noise.

I just retraced the route with the radio and if I put it right next to the phone line itself, I pick up what I assume to be broadband activity; a few inches away and there's no radiated noise apparent anywhere along the line.

[Rik]

Well, that's one more possibility ruled out then. The teleswitch may, of course, have become more noisy recently, or have started to radiate in a more sensitive part of the spectrum, but it sounds like it's not the issue.

[emvisi]

An update: my connection has been solid all day (of course) 

OK, the line stats aren't anything to write home about, but at least it's maintained sync. That's progress.

I have some new filters on the way, along with a spare router, so if the connection falls over again I'll be back on the diagnostics. I do wonder whether my router is suffering from good old dry-joint noise susceptibility on the PCB. Todays cooler ambient temperatures and the fact I've moved it to a less enclosed location might have temporarily cured things. Hard to say, unless I give it the hairdryer test (might do that, with a spare router coming).

One useful side-effect of noise-hunting is that I noticed the upstairs phone extension (currently disconnected) runs right past the noisy radio teleswitch. I'll re-route that before I reconnect it, using some Cat5e cable I have knocking around.

[Rik]

Sounds like you're on the right tracks, Mike. 

[emvisi]

Bah.

Lost sync at around 10:15 this morning, after almost 38 hours connected. I whizzed round with the MW radio to check for any new noise sources and heard nothing. The router resynced at 512 kbps; noise margin was up and down like a yo-yo, between 0 and and 24dB and settled, after a few mins, at 24dB

Work was a bit slow for the rest of the morning.

Anyway, the spare router showed up and I switched to that one at around 1pm. It synced at 4128 kbps, with line attenuation at the usual 42dB and a noise margin of 14dB (now 12dB). Unfortunately a BT speed test confirmed that the IP profile has once again bombed down to 350 kbps.

Now waiting to discover whether the replacement router fares any better with line noise.

This is such fun 

[Rik]

  for you Mike. The only good thing to say is that your profile should recover quite quickly with that big jump, ie hours rather than days.

[emvisi]

Thanks Rik.

Unfortunately it just got worse: disconnected for over 20 mins now, and won't resync. Patience evaporating...

[Rik]

Contact support now, ask them to look at what's happening from their end, it may give a clue.

[emvisi]

Just spoke to Brian: it seems BT may actually be in the process of switching me to the new cct, having cancelled the work 3 times because of a phantom open order for a new line.

Kill or cure, then

[Rik]

 

[Sebby]

Indeed...

[emvisi]

Still no connection

[Rik]

Get on the phone, Mike, if you haven't already - they're only there another five minutes.