Using Banshee 2.4.0, There is a setting:
Additionally, you could:
- Right click on All Artists then click Edit Track Information
- Go to the second tab, Extra, and fill out as follows:
This will take a long time, depending on the size of your library, but will edit every single song (unless the id3 comment tag is already a space, in which case, you could put something else there if you thought it necessary).
If, after this is all said and done, you are still unhappy about the state of the metadata (id3 tags) of your music collection, you could download Musicbrainz Picard. This program queries the Musizbrainz server and fills in and attempts to fix the metadata. I have had mixed luck with it. Check youtube for tutorials.
sudo apt-get install picard