Still not convinced that this was the whole issue but apparently my backup was still running and copying files over the network, it's a 1gbps router though and the server is only 100mbps so that shouldn't cause a problem. Cancelled the backup and will see if it seems to make a difference.
Edit: annoyingly it seems to make a difference, but I can't guarantee that the connection would be fine.
Edit(2): A quick search online says the races are not server based but P2P, so I guess it was my connection speed letting everyone down. If anyone is still around I can re-host and try again.
Edit (3): OK well we're leaving it for tonight, gutted that we didn't get anything and it was my connection. Going to try and work out why that caused a problem at all, and I assume that the three of you in the states will be busy at this time tomorrow. Arse. I wanted to drive my Volvo. :lol: