Modem or are you just using wireless? Mine used to do that some years ago, fixed it now but at the time i got around it by removing the wireless and simply using a good old cord.
Thanks for the advice, but it was the modem, it was making a nice crackling noise like it was on fire. I'd reset it and it would kind of work for a couple of days and then go tits up again. I do use wireless and that is working really well. If I was to run another cable thru the house I think my wife would kill me in my sleep. Cheers,Brian Guy