When I try to remove the tags using either Tag Remove or by directly editing the tags, it is only possible to change the first of the tags, not the others. After a Save, they come back when the file is reloaded.
I have upload one offending such file to
If I am being an idiot here and this actually works as it should, please let me know.
I have learned from forum messages, that it is possible and allowed to remove superfluously tags. In your case it looks like you have to do Tag Remove [Ctlr]+[R] the stacked tag sections four times until only one tag remains.
Mp3tag shows 5 FLAC tags and an embedded image. After using Ctrl+R the first time, it shows 4 tags and no image. Using it repeatedly after that (even if you quit Mp3tag and load the file again) it never deletes any more.
Using metaflac --list on the original file does indeed show 5 VORBIS_COMMENT blocks in this file.
Using metaflac -list on the file after Mp3tag has worked on it still shows 5 VORBIS_COMMENT blocks, the first of which contains 0 comments. So what Mp3tag is actually doing is just emptying the first comment block, then not counting it among the tags displayed by %_tag%. If you save the file again in Mp3tag (which will populate the first comment block with what it thinks are multiple fields from all of the other blocks) then Mp3tag will again show 5 tags.
Mp3tag's Ctrl+R should:
Completely remove a VORBIS_COMMENT block, not just empty it.
Each time Ctrl+R is used, it should remove one comment block. Either the first one or the last one. If given a choice, the last one (numerically) in the file would be best, as the first most likely has the most/correct metadata.
I've tried it with the example file and got the same result.
I assume that the file has been corrupted by some illegal processing before, because there are some tag field entries in either 8-fold or 5-fold copies.
Foobar 2000 can remove the flac tags completely.
Perhaps not a bug. But it would be good if Mp3tag handled the situation better. Unfortunately, the way it works now only makes the situation worse. The problem is that Mp3tag reads data from all vorbis comment blocks, but it only writes to the first one. Handling the situation better would be to only read and write the first vorbis comment block and completely ignore the others. For instance, this is how Winamp handles this file - the user never has any indication that there are additional vorbis comment blocks, and can add, edit and remove fields. And, of course, since the FLAC file is not corrupted in any way, it plays fine as well.
Being able to fix the metadata in files like this would be a good addition to Mp3tag, just as it would be better if there was a proper way of removing ID3 tags from FLAC files without having to resort to Ctrl+R, Ctrl+V. Since metaflac has no problem reading or removing the extra vorbis comment blocks, I would think libflac can handle them without a problem.