actually most of the time its to do with your internet connection, as i cant play BFME 2 or ROTWK after 4:30pm GTM as my internet connection drops for 2mb to 0.5mb which is really bad lol sometimes its worse than dial up !!!!, however im am getting a new provider and 16mb broadband soon so i wont have anymore problems, this is the actual cause of the annoying "log in timed out" message.
So the best thing to do is to get an internet bandwidth checker, i use: http://speedcheck.ispconnect.co.uk/Its really good an accurate, so try to find out the best time to play when your connection drops. I find that i cant play online / log in if my con is 1mb or less.
Hope this helps