A recommended fix for Windows Media Player 9 Series is out today:
When you are playing content from a network source, Microsoft Windows Media Player 9 Series may quit unexpectedly (crash) if Windows Media Player briefly loses the network connection and then tries to reconnect.
If you are using Windows Media Player together with a host application such as Microsoft Internet Explorer, and Windows Media Player is embedded in the host application, the host application may quit unexpectedly if the network connection is lost.
You can find the fix HERE.