A few listeners using the most recent versions of Flash 9 on Firefox on Windows have reported problems playing audio on the blog as well getting youtube to play more than 2 seconds of any given video (a problem quite a few other people seem to be having). We are looking into the problem.
In the meantime we recommend:
1) Downgrading to Flash Version 9,0,47 available here: http://blogfiles.wfmu.org/DG/flashplayer9r47_win.exe
2) Clearing out your cache.
This seems to solve the problem for most people. Give it a try.