I have an album tagged with "album artist" & "artist" and the corrosponding columns in the foobar display.
The "album artist" enrty is consistant for all tracks (Various artists) and the "artist" entry is differant for
for each track. The problem is that the "album artist" entry is replaced every time by the "artist" entry in the
column and also for the entry in Media Library.
Update #2. Setting the tags to unicode shows them correctly in the columns but still not in the media Library.
What code are you using to display the artist/album artist?
To display only the value of ALBUM ARTIST, you'll have to change instance(s) of %album artist% with $meta(album artist). This is because %album artist% checks ALBUM ARTIST, and displays what's found; or moves to ARTIST and displays what's there.
EDIT: You should check and see if this solves your problems, at the very least. Your problems does indeed seem odd.