I was about to post a bug report because of a strange behaviour I noticed while trying to play some .M4A files :
I burnt all of my .M4A files on a DVD, but for some reason, I was unable to play some of them : by right clicking on the files or the folder, or even by double clicking on them.
Even weirder : some appeared in the playlist window while some never.
If I put them on my hard disk, no troubles at all.
With your latest update (as of may 06), all seems to work well.
Just wanted to let you know about this, as I haven't read anything about this issue (and I thought that it was something that you could have wanted to know).
So : Many thanks for your great work!