Computer speakers only work with Audacity

I just loaded Audacity on my computer last night and used it to record an album. I listened to the album through the computer speakers while recording. I have the USB cable and the dual RCA cable to mini plug adaptor attached to my turntable and computer. This morning I cannot get any sound from the speakers for I-tunes, YouTube, etc, as the speakers now only work with Audacity. The fix listed in the manual (ajust audio properties) did not help. I am using version 2.0 on the Windows XP computer. How do I get the speakers working for applications other than Audacity?

Thanks for the help.

See here in the Frequently Asked Questions: http://manual.audacityteam.org/man/FAQ:Playback#usb