Apple Music Mini Player Won't Show Current Song Title and Artist
Piggy backing off an old thread—it appears this happens due to the keyboard shortcut setting "Use keyboard navigation to move focus between controls" which I find indispensable when quickly navigating system prompts with the keyboard alone (e.g. confirming a file deletion).
A few "fixes" were suggested that were a little tedious—the simplest is to use the offending keyboard navigation focus option.
Simply Cmd+Tab to Apple Music, then Tab twice—his moves the focus (red glow) away from the volume and output buttons, and the song title and artist will reappear.
iMac Line (2012 and Later)