iTunes loses its path to some song files

I am running iTunes 10.7 from 2 computers (only one at a time). The iTunes application files are on a NAS server, in the same place as my song files. Recently, some (not all) references to song files have got lost. For example, iTunes has recorded one song as if it is on ‘/Volumes/Macintosh HD/‘, and the next in its true location on the NAS. I don’t have any drive called ‘Macintosh HD’, so it seems that the reference to that particular file has reverted to a default.
iTunes doesn’t think the files are missing - it just thinks they are in the wrong place. There is no error message.
I don’t want to delete and re-import the iTunes file references, because a lot of these files are .WAVs, so the metadata is in iTunes. Nor do I want to downgrade to iTunes 11, because I want proper Artist/Album/Song lists, not clumps of Album cover pictures.
Any suggestions? Perhaps I could initialise a disc as ‘Macintosh HD’, manually move the missing files, then move them through iTunes, but that seems like a time consuming and error-prone solution. One possibility might be to export, and so preserve, the metadata in some way - if so I will certainly need some suggestions.

Have you looked at the "library" entry under the iTunes File column (at least it's in my iTunes 12 version). It has menus for organizing your iTunes Library (your music files) and for capturing-consolidating stray ones. Apologies in advance if I don't fully understand your problem, and best wishes if this can be of any assistance.