For ages ny 2860, on Plusnet VDSL has reported:
Profile State UP Speed Down Speed SNR Upstream SNR Downstream
17A SHOWTIME 20000 (Kbps) 72212 (Kbps) 15 (0.1dB) 5 (0.1dB)
(with small variations in the Down Speed)

Overnight it changed to:
Profile State UP Speed Down Speed SNR Upstream SNR Downstream
17A SHOWTIME 20000 (Kbps) 61872 (Kbps) 6 (0.1dB) 5 (0.1dB)
...where is has remained for the last ~ 48 hours.

I've tried changing the faceplate in case that had gone faulty but no difference.

Any idea what could have caused this?

The strange thing is that it's the *Upstream* SNR that fas fallen from 15 to 6, so why does that hit the *Downstream* speed?

TIA

Mark

the dlm must find an unstable connection perhaps due to errors
try a different modem code (wan > general setup>dsl modem code)
or alternative try the vector firmware from here (has different modem code)
http://www.draytek.com/index.php?option=com_jumi&view=application&fileid=15&Itemid=583&lang=en

Modem code was ANNEX_1_548006_544401. I set it to the only other option, ANNEX_1_560816_552011 but it wouldn't even connect. Just sat on a state of TRAINING. So back to the original setting on which it connected to SHOWTIME within a few seconds.

But still with Upstream SNR at 6, rather than the 15 it has been on for the last ~ 2 years.

I only recently updated to 3.7.4.3, but that was several days before the unaccounted change in SNR.

Stuck for what to try next.

I had a sudden similar drop in SNR and speed on my 2820 which turned out to be a suddnen REIN repetitive electical interference noise. It turned out to be the Router power supply. The power supply was still working fine but something in it had gone wrong and was radiating interference which was upsetting the ADSL. A good learning curve - I also found that one of my new LED lights was also causing REIN interference when it was on although at a lower level than the Router power supply. Changed the router power supply and changed the brand of the LED lights from Chinese to UK and everything was back to normal.

Jon

Thanks Jon, v.interesting. I had wondered about something like that.

How on earth did you track it down?

I assume the interference could be occuring anywhere between you and the exchange as it's the phone wiring that's picking it up? Mine runs all through the guts of a 4-story building so untold scope for sources of interference.

Quiet line test is silent but it could be rf. Any idea what frequency range to look for? Perhaps I can wander about with an AM radio.

There is a basic video here, the frequency is 612
http://support.zen.co.uk/kb/Knowledgebase/Broadband-Understanding-REIN-and-SHINE