Got connected FTTC a couple of months ago. D/l speed a tad over 4MB/s dropped to 3.80 over a few days. Suffering intermittent disconnections, my logs looked much worse than the apparent reality. Once I noticed the logs I could see that they were correlating with drops in the PPP session (some very short indeed), sync never lost.
Engineer visit today (that makes two who think one cannot connect with the modem alone, but I digress). Replaced some tinned aluminium wire in my socket (which he said was a 'no no') with copper and replaced the modem; the first batch was faulty. He then arranged for my profile to be reset. 72 hrs of training to go, cannot use the BT tester during this period.
I can download at 4.36MB/s now. I was his first call of the day, normally when I am given a 08:00-13:00 hrs slot I wait for ages - hopefully a good omen.
Many thanks go to ADSL24 support for agreeing that there was a problem without any effort on my part.