When loading any music by the band W.A.S.P. anytime I load the tags or save any information MP3Tag will "duplicate" the text in Artist, Album Name & Genre.
For instance if I load the album "The Best Of The Best 1984-2000" which currently has Artist "W.A.S.P." and Genre "Heavy Metal" it will instantly change to:
Album "The Best Of The Best 1984-2000\\The Best Of The Best 1984-2000"
Genre "Heavy Metal\\Heavy Metal"
Even double clicking one of the affected tag fields replicates the issue.
Perhaps to do with the fullstop at the end of W.A.S.P.? This is the band's "official" name.
Need any more info just ask. MP3Tag is upto date.