I don’t have any good news for you here. Mine just started doing the exact same thing today. I am using a Mp3 but I also converted it to a Wav just to be sure. So it still works when I double click it inside the project properties tab, but on the time line the audio levels move but no audio. So here is a bump for the thread because this is driving me nuts.
Mac Pro
AE version 7.0.1
2x3ghz intel
5 gb ram
Kyle Warren