Strange that as I am experiencing very similar problems and am also with Xilo. Up until Christmas 2010 I was with UKOnline for about 8 or 9 years and had been getting steady 1mb service due to line length. Then UKO (Sky) removed their service but Sky wouldn't let me transfer due to not being able to receive 2mb BB so I eventually went with Xilo. For 2 to 3 months I received 1.5mb service without a fault and then all of a sudden it dropped to .5 mb so I raised a fault and was told it was probably due to my line degrading. Anyway they raised a fault and lo and behold 2 days later we're back up to 1.5mb. 2 days ago I lost sync totally and contacted xilo who said again it's probably due to my line length and the degradation of the line ([censored]) so raised a fault with C&W. BB is currently back but now at .5mb again. My immediate neighbours are still getting 1 to 1.5mb and whilst my BB was offline I paid for a days worth of BT Openzone which connected at 1.5 mb so someone somewhere is having a bit of a laugh.

The issue with your line is length. Currently sitting at over 7400 meters.

We've offered an engineering visit on the previous fault but the service appeared to return of its own accord, but after your most recent report, it has been re-raised again and C&W have this in hand at present and we're due to get an update from them today.

Matt

I am aware that the issue with my line is the length and always has been. What I cannot understand is that for years I had a stable 1mb connection with no problems whatsoever (on LLU). Since changing provider I have had stable connections at 1.5mb (as have my neighbours with similar line lengths) but all of a sudden my speed drops to .5mb. I am not blaming anybody for this but cannot understand why all of a sudden after 8 or 9 years I am now getting speeds of .5mb compared with the 1mb I used to get. In all the time I was with UKO I had no need to call their technical advice at all regarding speed or connection issues. If my current speed was around that I used to receive with UKO then we wouldn't be having this conversation.

Additionally, I am convinced that my line length used to be 6200 metres from the exchange so wonder if something has changed without my knowledge. SYDR has recently gone live in parts of the village where I live and this issue has only manifested itself since then.

We can't rule out something happening between both ends of the cable but likewise, just because it has worked at 1Mb for that long does not mean there won't ever be an issue or something new causing interference on the line, for example.

Matt

On UKOnline you were probably on SRA, (Seemless Rate Adaptation), so the sync speed could very well have been rising and falling between those two extremes without you noticing.

No other provider, not even Sky, uses SRA, so if you get a sync speed drop due to noise then a manual re-sync is needed. Perhaps at intervals, but not frequently, until the noise source is turned off.

I assume at some time in the past you have ensured there are no possible noise sources within your control? Extension cabling; bell-wire; filter checks; Sky Box double-filtering and so on?

Edited by RobertoS (Wed 27-Jul-11 12:44:34)

I've checked as much as I possibly can with my limited technical expertise. I don't have a sky box and have eliminated all extensions by plugging the router directly into the main BT socket which is an old type socket without a separate test socket.

Just a thought: if the signal quality is varying, and if that was leading to sync speed changes, and if it is still similarly varying, without SRA it will surely cause a similarly-patterned variation in SNR? Suitably motivated geeks can use appropriate tools to graph SNR vs time (and possibly error counts vs time) and see if there is a pattern?

There's loads of info like this inside every DSL modem/router (it's part of the spec), and the DSL protocol ensures that what the customer end knows about that kind of thing is also notified to the DLSAM in the exchange from time to time. From the DSLAM to the ISP (perhaps via the wholesaler) it is of course generally ignored... self-install DSL all too frequently apparently also means self-diagnosed DSL.

Still, it's only been ten years or so, you can't expect BTw or their LLU equivalents to move that quickly (though apparently Bulldog had some clever facilities for this kind of thing back in their day, whenever that was).

RouterStats, or RouterStats Lite lower down that page, are brilliant for this.

When I was on ADSLx I ran Lite all the time, at a 5-second sampling interval.

In reply to a post by Anonymous:

Still, it's only been ten years or so, you can't expect BTw or their LLU equivalents to move that quickly (though apparently Bulldog had some clever facilities for this kind of thing back in their day, whenever that was).

C&W (ex-Bulldog) do alter the interleaving at sync time but I have never seen SNR change from what is fixed up at 9db/Interleaved unless you've been placed on a rate profile (starting at 2-4Mb).

Matt

Engineer attended on time and couldn't find a fault either with the line or the house. He changed the faceplate and I now have the 1.5mb that I used to have with better line stats. He also said there wouldn't be a charge but we'll just have to wait and see having read some other posts regarding engineers visits. (I did make hom a cuppa though so might be ok!)