Problem with multiplayer load up

[79TransAm]

Ok So I find a multiplayer game I want to play in. My firewall is turned off and everything is allright. The host clicks to start game I go to the load up screen(where it gives you your orders) and then it flashes to the black initalizing screen and it just sits there and the game freezes and i have to ctrl alt delete to exit the game. Any reason why it does this, happens id say about 70% of the time I try to play a multi player game in SH3

Thanks