I have the same problem. Here are my symptoms:
Express Scribe loads without any problems. I browse to a folder, get a list of files. Click on a supported filetype. No matter what kind of file I pick, I cannot get the file to *play*.
I have tried mp3, wav, aiff, aif.
I am able to write in the text box below, and to scrub the audio playhead (this updates the timecode in the menubar and in the application). I can also scrub the speed scrollbar, but it doesn't help anything.
When I click play, the play button goes gray (seems like this is the selected state). It stays gray, but the playhead does not advance. No sound comes out obviously.
I am running Express Scribe 4.05 on Mac OS X version 10.4.10.
Thanks for any help that you can provide.