There's a related problem, involving LAME -- it writes replaygain info to the file header. VLC displays it; mp3tag thinks it's an APE tag; but removing APE tags doesn't get rid of it.
According to the LAME spec, "nothing" understands this tag - yet - but to avoid any issues in future I'd like to get rid of it.
If there's a way for mp3tag to remove the LAME replaygain header, that would be really useful.
You could test if one of the named utilities helps to clean up - see here:
Is it possible that you share such a song?
If you want, you can send the link to the shared file in a PM. Maybe we can find out what kind of tag (ID3, APE, something else) is used.
I never had the case that MP3Tag thinks that the replaygain-part of the lame-header is an ape-tag.
BTW:
The lame-parameter --noreplaygain disables writing raplaygain to the lame-header.
Well, I can assume then that the APE tags I was seeing -- which were very sparsely populated -- came from some form of magic. These were files I had ripped using Easy Audio Copy, which EasyAC compressed to both FLAC and MP3 after ripping. Maybe they have nothing to do with the LAME replaygain tags. I didn't see them in files I made some years ago with LAME 3.97 (even though those, also, have the track-gain tags).
Now that I know about the --noreplaygain switch, I can prevent LAME from creating the track-gain tag in future -- but that doesn't get rid of the many that I already have.
dBPoweramp Music Converter also features the ability to calculate and add tags for track and album gain, as well,as adding the choice of either for iTunes if you are setting up your files for that format. All works very quickly and reliably for me without impacting the actual audio file. Works with lossless and lossy formats.
GB
You can use foobar with right click->Utilities->Fix vbr mp3 header to get rid of the replaygain-part of the header.
If you don't want to know which tag is used (and share such a sample file), you can maybe get rid of the replaygain information with this tool MP3Gain. There is a command line and GUI version of the tool.
On the command line you can use
mp3gain /u song.mp3
That is no tag. The lame replaygain-information is in the lame-header.
If this is true, maybe the tool "LameTag" can help @markf to solve his problem.
If someone else is interested in the technical details
http://gabriel.mp3-tech.org/mp3infotag.html
Please read the section "byte $B5 MP3 Gain" carefully.
Thank you for the suggestion. I will try that and report back.
I can't figure out how to share a copyrighted file without breaking the law. But I am slowly working my way through the various suggested programs to see what happens, and I will report anything I find out.
Apparently LameTag is not available for download. The link on the page https
phwip.wordpress.com home audio returns "not found".
OK:
mp3val finds nothing wrong with the files. This is as expected, since LAME is known to be a good encoder.
mp3diag sees the LAME header, but does not report the existence of the Track Replaygain information. (VLC confirms that it is there.)
foobar2000 "fix VBR header" does remove the LAME replaygain info (VLC confirms it is gone).
Unfortunately I cannot try lametag because dropbox cannot find it.
Thank you all for your assistance. Now I know what to do, both in future and to clean up the files I already have.