When I cleared the lyrics option this 'error' did not occur.

Ah. I believe ID3Lib's (and thus Emplode's) handling of Lyrics tags isn't fully functional; in particular, it can read them but not write them. This means that if you've got artist or title tags in Lyrics format, they will be "stubborn" against all ID3Lib-based efforts to remove them. To fix such stubbornness, you either need to find a non-ID3Lib editor that understands Lyrics tags, or an ID3Lib one that strips them.

Peter