In reply to:
nope, the adsl filter was one supplied by adslnation and cost �12 so hoped it was a good one.
Oh, it's probably a very good one, but it can't do anything about your extension wiring. What is happening is that your extension wiring (especially the ring wire) is picking up noise (mostly in the form of MW radio stations), and it is being fed back to your ADSL modem, and this noise is affecting your ADSL. Because MW radio signals are always stronger at night, the noise on your line will always be worse at night.
The prime purpose of a plug-in ADSL filter is to stop the ADSL frequencies from interfering with the phones, faxes and Sky boxes in your house, and it also prevents the phones from loading the ADSL signal. A plug-in filter cannot and will not stop AM radio noise picked up by your wiring from getting back to your ADSL modem.
A faceplate filter on the other hand will filter noise from the extensions, and stop it getting back to the ADSL modem, as long as the extensions are fed from the filtered side of the faceplate. You can buy a fitered faceplate from ADSL Nation that contains the same filter technology as the XF-1e, which should make a difference to your line noise at night, and it will also dispense with the need for any other filters in the house, if the extensions are fed from the filtered side of the faceplate.
Edited by deleted (Sun 18-Nov-07 10:37:43)