If MP3GAIN is used to set the level of an MP3 file, then tag fields MP3GAIN_MINMAX, MP3GAIN_UNDO, REPLAYGAIN_TRACK_GAIN and REPLAYGAIN_TRACK_PEAK are added. From that point, if I open the MP3 file in MP3TAG it does not display any tag information. However dbpowerAMP sees all of the tag info without problem, and if I open the MP3 file with dbpowerAMP's EditTag, but then hit 'OK' without changing any tag fields, MP3TAG is then able to read the tags. It seems that dbpowerAMP is reordering the fields in the tags. But why is MP3TAG sensitive to this ordering?
I've can supply a file showing the symptoms, but the forum won't let me attach it.