Streaming video problem

I have just set up a wireless home network moving on from just the one
computer using a USM modem to Tiscali but have a strange situation regarding
downloading streaming video.

My preferred video player is Windows Media Player.

When I download streaming video to my desktop which is wired through the
modem/router I have no problems. However, when I try to download streaming
video on any of my wireless laptops using Windows media Player nothing
happens. If I use Real Player then I can download streaming videos OK.

If I connect my laptop to the internet using my old USB modem there is no
problem with Downloading streaming video so the computer is not at fault.
Because I can dowload streaming video to Windows Media Player on my desktop
through my new modem/router there is no issue there.

Can anyone explain this issue which is only happening with Windows Media
Player.