collectiongain fails to recognize albums for m4a (aac) files

[jtbr]

When I run collectiongain on an album containing (at least some) AAC files, the individual tracks are always marked as single tracks rather than as an album:

~/Music/Fiona Apple/Tidal $ collectiongain --regain -d .
Collecting files ...
  [1] 08 The Child Is Gone.m4a |<single track>
  [2] 04 Criminal.m4a |<single track>
  [3] 09 Pale September.m4a |<single track>
  [4] 03 Shadowboxer.m4a |<single track>
  [5] 05 Slow Like Honey.m4a |<single track>
  [6] 02 Sullen Girl.m4a |<single track>
  [7] 10 Carrion.m4a |<single track>
  [8] 06 The First Taste.m4a |<single track>
  [9] 01 Sleep To Dream.m4a |<single track>
  [10] 07 Never Is A Promise.m4a |<single track>

Even though both the artist, albumartist, and album are set to be the same for all these files. At first, albumartist was not set, and I thought that could be the problem, but I get the same result when it is set to equal artist. These files do not have MusicMatch tags.

[jtbr]

I noticed PR #25 which seemed like it might solve the issue. Indeed, after manually patching my install, collectiongain seems to be working correctly for these mp4 files.

[chaudum]

I'm happy to hear that #25 works with your files. m4a support should go into the next release.