Huge drop in upload speed (SNR)

I was originally refused ADSL at the initial rollout because my line length is 3.7km.
However, after a change of ISP and much persuasion, BT agreed to try to install.
There was no problem with my "500kbps" service using the "stingray" modem.
A few years ago, I bought an Edimax ADSL2+ router and the connection stats were:
Down 576kbps, Att 47.0dB, SNR 37.0dB.
Up 288kbps, Att 31.5dB, SNR 26.0dB.
I have been using this router ever since.
It seems I was actually on a business broadband package, but changed to a domestic "up to 8 Meg" package.
BT line test said I could get 512kbps, with maybe 1Mbps on ADSL Max.
However, at the changeover I got the following:
Down 6688kbps, Att 44.5dB, SNR 6.5dB.
Up 448kbps, Att 31.0dB, SNR 22.0dB.

That's how things have stayed for years, with the occasional resync if the downstream SNR drops below 5dB.
BT did send a Home Hub when I changed package, but it would only connect at just under 3000kbps so I changed back to the old router. I could put up with a resync at about 2am every day!
However I've been away quite a few weeks and now I just tried sending an email with attachment.
It seemed to take forever so I logged into the router and these are the stats:
Down 6880kbps, Att 44.5dB, SNR 6.5dB.
Up 64kbps, Att 29.0dB, SNR 7.0dB.

There has been no alteration to the connections and the router and the laptop are the only electrical appliances plugged in at the moment - not even the fridge.

The router model is Edimax AR7064g+A. It has a "conventional" rather than switch-mode power supply adapter.

I'm going to borrow another router to try, but this looks like it's an issue external to the house at the moment. Any thoughts?

Three possible problems

1. Could be some really nasty noise being picked up by the line and at the low frequency end so only affecting upstream.

Can you see a bit loading map from either router?


2. Could be a failing/failed modem in your router - try powering down and leaving for 15 minutes and then try again. Or try the BT HH and see if it improves. There could also be a problem on the input filter stage of the modem (not the standard filter but an internal one which you do not see).

3. Card failure at the exchange.


You need to prove it is not in the house first so ensure nothing else is connected to the phone line and if you can, connect to the hidden socket behind the master face plate.

With connection/disconnection &c you may see a drop in your downstream sync - don't worry too much it will recover

Thanks for the reply.
I dug out my BT HH and that has showed that the problem was my router.
It's stats show:
xDSL linestate up (downstream: 5024 kbit/s, upstream: 448 kbit/s; output Power Down: 19.5 dBm, Up: 12.5 dBm; line Attenuation Down: 45.0 dB, Up: 25.5 dB; snr Margin Down: 15.5 dB, Up: 23.0 dB)

448kbps at 25.5dB Att and 23.0dB SNR is back where it should be.

Interesting that it's connected at a higher downstream rate than it used to though.

Off to try and fix my Edimax router now....didn't think that would have been the problem at all!