Plugins problem

i did re-install last week for my vista home but not sure whats causeing this problem.when i go to play a local radio station it says to click to download plugin.i did that but the plugin fails to work even manually says no suitable plugins were says unknow plugin {text/plain}can someone help me with this thank you.

where i got it fix.i was useing firefox 3.0 but i guess they didnt have a plugin for it so installed 2.0 all over agin and went to the site that i came back up but this time they had a plug for it so everything is ok now.