Due to indeterminate order with which plugins run these two don't play nicely alongside each other.

From http://forums.musicbrainz.org/viewtopic.php?id=3013, changing

match = re.match(r"([\s\S]+) feat.([\s\S]+)", metadata["albumartist"])

to

ch = re.match(r"([\s\S]+) [fF]eat.([\s\S]+)", metadata["albumartist"])

(and consider similar changes in other feat-related plugins) would allow these to work better together.