I had problems streaming through a router because of the built in firewall in the router itself, after talkin to a few friends I bought a switch to elimate the router portion of it and it works amazing! you still have to use the router though in order to use the PC and 360 cauze the router adds or splits the IP from your ISP so you still have to keep the router
http://img518.imageshack.us/i/networknotepaddudeunterpc7.png/dont mind the switch on the right, the main is where the PC and printer enter the switch then go into the bubble which would be the router then the router goes to the net
I had the same problem awhile back as well the switch is just like a router but alot dumber since it doesnt have any kind of features (built in firewall), I have 2 360's and they r running in 2 different rooms and due to it I can play online, stream music/movies all at the same time