Unstable Virgin ADSL - Help!

Urban Reflex · 20 Aug 2009 at 01:22

Alright geezers, I need your help one this one.

A good friend of mine is having trouble with her Virgin ADSL connection. She has problems pretty much every night, and her symptoms are that the connection becomes slow, and disconnects.

Her router is the Netgear WGR614, and whenever she has issues the internet and DSL lights flicker and/or go out or turn red. We checked her line attenuation, and it's 60db with a downstream SNR of 12db. A speed test reveals 1567kbps download and 497kbps upload, and she lives about two miles from her exchange.

Any idea what the problem with the connection is? She's connecting to the router wireless, could it be interference? Or could Virgin be throttling her connection?

Aedus · 20 Aug 2009 at 02:17

They shouldn't throttle her connection unless she's doing a lot of downloading during the day, even then it shouldn't disconnect, so I guess it's interference.

tolien · 20 Aug 2009 at 17:47

The WGR614 doesn't have an ADSL modem. Are you sure it's ADSL?

If the DSL lights are going out, she's losing sync, so it has nothing to do with either the ISP or the wireless network connection. Try the router connected to the master socket with no extensions.

Urban Reflex · 21 Aug 2009 at 01:56

Aedus said:
They shouldn't throttle her connection unless she's doing a lot of downloading during the day, even then it shouldn't disconnect, so I guess it's interference.

Interference.. you mean on the line right?

tolien said:
The WGR614 doesn't have an ADSL modem. Are you sure it's ADSL?

I am... on further inspection it appears to be the Netgear DG834G. Women eh?

tolien said:
If the DSL lights are going out, she's losing sync, so it has nothing to do with either the ISP or the wireless network connection. Try the router connected to the master socket with no extensions.

Losing sync with the ISP you mean? She's plugged into the master socket and is only using a (roughly) two metre cable from the microfilter to the router. She's also tried changing the microfilter.

Aedus · 21 Aug 2009 at 02:05

Does it happen at the same time every night? Or does it occour throughout the day too?

tolien · 21 Aug 2009 at 10:44

Urban Reflex said:
Losing sync with the ISP you mean?

No, ADSL sync, i.e. "with the exchange". Does she have any other extensions?

Other than that, there's not much more to do at the customer end. She needs to speak to the ISP.

Urban Reflex · 22 Aug 2009 at 01:38

Aedus said:
Does it happen at the same time every night? Or does it occour throughout the day too?

She doesn't use it much during the day, but on the few occasions she has it's been fine. It seems to get steadily worse as it approaches 2am.

tolien said:
No, ADSL sync, i.e. "with the exchange". Does she have any other extensions?

No, all she has is a phone and the router connected via a microfilter to one socket. Nothing else in any of the others.

tolien said:
Other than that, there's not much more to do at the customer end. She needs to speak to the ISP.

Yeah, I was afraid of that :/ I fear there's not much they'll do for her, or that she'd get any results changing supplier.

Mattus · 22 Aug 2009 at 01:51

It sounds like her noise margin is dropping too low. 12dB is fine, but I'm guessing you checked it in the daytime, and lines generally get worse at night. Can you check the noise margin again, just before it usually disconnects?

If that is the problem, you need to ask the ISP to raise the target SNR. It's a shame because she has a long line and hence poor enough speeds already, but stability > speed.

Urban Reflex · 22 Aug 2009 at 03:04

Mattus said:
It sounds like her noise margin is dropping too low. 12dB is fine, but I'm guessing you checked it in the daytime, and lines generally get worse at night. Can you check the noise margin again, just before it usually disconnects?

Well it seems to be a constant 12db SNR / 60db attenuation during the hours she's using it (2300 onwards), but I'll see if I can get her to check it when it does actually disconnect and during the daytime.

Mattus said:
If that is the problem, you need to ask the ISP to raise the target SNR. It's a shame because she has a long line and hence poor enough speeds already, but stability > speed.

The target SNR? I found this guide on how to do it on her router - would this work or does the ISP have to do something their end? I'm guessing by the way you worded it it'll (hopefully) give her more stability while sacrificing speed?

tolien · 22 Aug 2009 at 10:50

When it disconnects you won't get anything. As Mattus says, it's just before it disconnects you're after.

The target SNR margin is typically set on the DSLAM (i.e. at the exchange) so the ISP needs to make it happen but it would improve stability at the expense of making her connection slower. That link is for a different router model again.

No, all she has is a phone and the router connected via a microfilter to one socket. Nothing else in any of the others.

So there are extensions, but she's not using them? It's probably worth trying with just the modem and no filter or phone, and if there are extensions not being used they should be disconnected as well.
The "one socket" should be the master socket here too.

Urban Reflex · 24 Aug 2009 at 10:55

Okay, so last night we unplugged all unnecessary devices, extensions, etc. It was just the modem router plugged directly into the master socket.

This didn't make any difference, however - disconnections still occured as they have been doing. Her SNR was a steady 9.X throughout, both just before and just after the disconnections.

It's really frustrating when you everything you try has no effect, but I really appreciate you guys helping me out on this. <3

tolien · 24 Aug 2009 at 11:14

So the SNR margin doesn't change, but the DSL light's definitely going out (i.e. it's losing sync)?

TheCenturion · 24 Aug 2009 at 12:41

I have virgin, fibre optic. using ethernet to my belkin, I have no problems, if I use wireless, I get problems not only connecting to the belkin, but in the last couple of days the modem has been disconnecting from the net as well. I'm going to have to ring them up.

tolien · 24 Aug 2009 at 14:52

So you have nothing related to this thread at all. Great.

Urban Reflex · 24 Aug 2009 at 17:34

tolien said:
So the SNR margin doesn't change, but the DSL light's definitely going out (i.e. it's losing sync)?

Exactly. If the connection is just being ****ty, the lights will flicker. However, if it drops altogether then the internet light will go red and the DSL one off completely. SNR and attenuation are both pretty constant.

tolien · 24 Aug 2009 at 17:44

Try another router? You can pick up a DG834GT (especially the ex-Sky one) pretty cheaply, it would let you mess about with the target SNR margin and it would eliminate the DG834G being faulty.

$anch3z · 25 Aug 2009 at 07:11

With the amount of attenuation you may be limited with work that can be done to improve the connection. DSLAM's have SNR values from 6db to 15db, if its available, ask for the target to be set at 12db but not on a rate adaptive profile. With the attenuation at 60db and the sync rate you quote it sounds like an LLU dslam (usually BT's Dslams sync at 448 kbps - no llu). This is a good thing as there is usually a better choice of line profiles available on LLU, also provided you get to speak to a decent tech you should be able to the profile changed on the fly until you find one that does not error. Another thing to look for is upstream or downstream crc, hec & fec errors, upstream is often indicative of internal wiring or router problems.

Good luck

Rabtech · 25 Aug 2009 at 08:43

The 497Kb/s on the upload would mean that your friend is either on a BT Wholesale based Business package or more than likely Virgin LLU provided by Bulldog/C&W.

As tolien mentions, try a completely different router as the 834G might be getting a bit long in the tooth on ADSL2+. You could also try updating the 834G to its latest firmware if you haven't done so already. If the line still drops using a different router, get in contact with Virgin as they may be having DSLAM issues with the line card/port.

Urban Reflex · 27 Aug 2009 at 03:36

Alright guys, sorry for the slow reply. I learnt her my old router, one of the Belkin G modem routers. Tried it over the past few nights but to no avail, it's doing the same sorta thing.

She's gonna get in touch with Virgin and see if they can fix it, but to be honest I'm not sure if they're going to be much help - I've never had good experience with the tech support of broadband companies.

Thanks for all your time and effort though people, it's really appreciated. I'll let you know if the situation changes at all.