Very interesting. I have had many problems with disconnections, to the result that I have had plenty of technical advice from Tiscali [my ISP] Thomson SpeedTouch [the modem]BT [line supplier].Whilst the problem is still there,it is not as bad as it was, this is after trying out various suggestions. In fact Tiscali substituted the Thomson modem for a Sagem, as there was a known problem with the SpeedTouch and my particular motherboard chipset.
BT have initially stated that the problem is not theirs, but I ran an exchange check via click here and found a fault with my providing local exchange.I am awaiting further information from BT. Like Ange, most of my disconnections are mid to late evening,which the Nod report on my exchange and line would possibly confirm.
Another factor that I learnt was the power usage of modems. All are not the same,some are more power thirsty than others, and this can possibly lead to 'drop-outs'and disconnections.
Might now consider a cheaper modem from the ebuyer range :o)