I experienced a strange behaviour when tagging brand new track -- lost tagging, when editing the track for the first time. The tracks were FLAC, I am not sure about other filetypes, yet.
- new album dragged into MM
- volume-levelling done
- tracks played, all playable
The following is show in the video: http://screencast.com/t/cqyfO9rD0W4
- switching to the folder (My Computer) tree
- select all
- edit File Properties for Disc and Album Title
- tags saved (the window is closed, and one can see a progress bar of saving the tags)
- a track played
- MM reverts all the tagging to the previous one
(end of the video)
Is that awaited, please?
Entering the disc number the second time is persistent, i.e. MM does not change to the previous tag anymore.