I listen to a lot of classical music, which often has multiple artists (conductor, orchestra, soloists etc), is there a way so to only submit the first artist to last.fm? (Short of removing the other artists). My library is getting messy  :( I'm sure it's possible, as the WindowsMP last.fm plug-in/desktop scrobbler does it.

Currently you'll have to edit the plugins/audioscrobbler.pm file : replacing the two occurrences of "title artist album track" by "title first_artist album track" should work. (One occurrence is for "now playing" the other for submitting a played song)

The current way of handling multi-artists in gmb is not perfect and I'm thinking about other ways, so that in particular the standard artist field simply contains the artist name written on the album, so that it can be used for last.fm and for display. And put the other artists names in a special field. Of course for classical music even the artist name written on the album is not so simple.

In the meantime maybe I should add an option for the last.fm plugin to select which artist field to use : artist, first_artist or album_artist