@dartgirl I'd had internet connection problems with TalkTalk for quite a while (short and frequent dropouts), but didn't bother doing anything about it until a couple of weeks ago. I got a live chat going with their H&S and said the connection kept dropping and that my 5 year old router was overheating, so could I have a replacement.
He didn't want to replace it until I said I didn't want my house to burn down over Christmas - at which point he changed his tune, sent me a new replacement router and got BT Openreach engineer to check the lines back as far as the main junction box at the end of the street. (The old router, a TG582n, does have a reputation for getting a bit too warm)
Using the tactic of a building burning down due to their faulty equipment may have been a bit nasty, but I've had no problems since.