One - and only one - artist won't show up in Artists list

New forum member and new SB Touch user - apologies in advance if this has been addressed. (I did search first.)

[I've edited this post as I've learned more info - this is the latest]

THE PROBLEM: I thought one artist - Led Zeppelin - wasn't showing up in the "Artists" list in my LMS library (and therefore on my SB Touch and in Squeezeplay). HOWEVER, it turns out that Led Zeppelin - and a handful of other artists - are indeed showing up, but they are all under the letter "V."

Why? Apparently because each of these artists has one song on a soundtrack album that's in my library, and for this album I have the "album artist" as "Various artists." So for some reason, even though I have more than 1400 Led Zeppelin tracks in my iTunes library, LMS is filing "Led Zeppelin" under "V" because of this one song.

Obviously I will have to experiment with some re-tagging here. But in the meantime, has anyone ever experienced this problem? If so, I would be grateful for any ideas or guidance folks can provide!

(P.S. My setup: Mac OS X 10.9.2; LMS 7.7.3; Squeezebox Touch with latest official firmware)