Will not record

Using Audacity 2.0.4 on OSX 10.8.4

Installation Successful.
But after pressing record and pressing play on youtube file, no audio is recorded in Audacity.
Please help.

Mac computers have no built in ability to record sounds that are playing on the computer.
See here for possible workarounds: http://manual.audacityteam.org/o/man/tutorial_recording_computer_playback_on_mac.html

I was having this problem as well. Steve’s reference solved the issue for me. I thought this was strange since I had been recording using Audacity without a problem. I did notice something though. If you look in Audacity Preferences under devices you will see a more current build for the core audio interface. I don’t know if this affected Audacity performance. I am back to normal and a happy camper.