a new version of flash, apparently really bad version if everyone's experiences is any indication, came out on Thursday, or later depending on your browsers update schedule or instantaneously if Chrome.
I post my instant solution that fixed my computer in a forum post in bw2, I have not experienced any issues with Idols before or after I 'fixed' my system. Many other bw2 people have reported success after doing the simple thing there, BUT I also am confused cause some people with the problems also have not had flash make that dastardly unannounced change.

http://forum.codenameentertainment.com/?thread_id=11984

if that doesn't work then try to use your operating system to uninstall flash and reinstall it, and/or uninstall your browser and reinstall that.

Oh, and I have not used the firefox browser for Idols since around the event just before the Christmas event when something there was unbearable. And I also have different browsers for different things, all open at the same time. I use Chrome for idols, sea monkey for bw2, and firefox for everything else facebook... Works well for me.