This is an interesting problem that I have also run into with previous software players I have used. Song titles that consist only of a punctuation mark, like the song called ? on the new Mark Pritchard album Under The Sun (VERY highly recommended by the way!) do not get indexed.
This must have something to do with the exclusion of certain punctuation marks for filenames, but since there is no limit to artistic freedom (you simply can’t demand that musicians take these technical limitations into account) I am in need of a workaround. Now some platforms have this ‘automatic replace’ sort of plugin in which you can set certain punctuation marks to be replaced by something that will index properly, but Roon doesn’t seem to have that function.
I have tried putting the ? between brackets, like this: (?) and I’m running an forced rescan right now to see if this works (almost 80.000 tracks does take a while, even on an incremental scan) but I prefer another solution altogether since the title of the track is ? and not (?).
Does anybody have any idea if this is at all possible?