Playing music by Genre - when it isn't

decided to let Plex play some music… selected by Genre (Jazz Vocal), I understand this is NOT by track, but by Artist/Album. First track comes on, I toggle on the shuffle icon, play swaps to a new tune, I walk back into the room and Billy Joel’s “We didn’t start the fire” is playing… UGH? He’s not showing in the Artist list that is being displayed. I checked the two albums and the tags are for Pop and or Rock. So HOW??

I can add that the interface for Music on the iOS app is less functional (or plainly more confusing) than the Web client. Wasn’t very helpful in looking into this problem.

How did you pick this? If it’s a filter, you can specify if it is Artist, Album, or Track.