Some tags are not being returned when MySql caching is enabled.
I don't know if it's specific to the files, it probably is. These are from a rather new release.
In the playlist at the links below, at the bottom of the list, most of the dido album is effected and I haven't figured it out yet.
Cached playist using idv1
Cached playlist with $getID3->clear_cache(); first.
Note the output correctly finds the tags when caching is disabled or reset.
Sources are available at: