I'm sure this has come up at some point and I hope I didn't miss something, but I couldn't find anything doing a quick search.
MMW 4.1.4.1709 only recognizes replaygain tags in mp3 files with id3v2.4 tags if they're in the following format:
replaygain_track_gain -1.9 dB
(lower case, 'dB' as unit)
E.g.: https://dl.dropboxusercontent.com/u/344 ... orking.mp3
I'm re-gaining the volumes using r128gain which has the EBU R128 algorithm. r128gain writes the tag as:
REPLAYGAIN_TRACK_GAIN -1.9 db
(upper case, 'db' as unit)
E.g: https://dl.dropboxusercontent.com/u/344 ... orking.mp3
Both are not 100% true to the specs, but imho MMW should be handling it.
To be sure it's not something else r128gain does, I changed the r128gain source accordingly and MMW reads the tags correctly. I'll submit a bug report/patch to r128gain too.
Reading replaygain tags in id3v2.4 not robust
Moderator: Gurus