Not running in theatre mode, that's just the track information bar below the track listings. It's an old skin (and probably the creator is no longer active), still it seemed to work fine last release. Can't really think what could be broken about the XML portion of it given that rechecking the show lyrics box shows the correct information. I mean, there's no actual code within the theme AFAIK. What's essentially a stylesheet shouldn't give a different result after disabling and reenabling an option.
Edit: There was an easier option. Switched to default skin, same issue. If a 'theme' is something different, I'm not running one. This isn't theatre mode.