Hmm, My Music Is Playing Musical Chairs..!

[pinchi22]

Has anyone else found albums within folders randomly and mysteriously moved to other folders?

Relevant facts:

1) Albums are stored on Synology 212J NAS.
2) Albums DO appear to be correctly saved within folders (eg, several Mozart albums do appear under Mozart folder when browsing NAS files).
3) However, albums have been shuffled randomly to other folders (eg, no Mozart album shows up under Mozart folder, only a single, random album when I select using control point).
4) I am using Naim v4.3 app as control point.
5) I am using "folder view" to find and select albums to play.
6) This problem doesn't occur using (Synology) Disk Station app as UPnP server.
7) I have re-scanned music, to no avail.

Many thanks in advance.
Signed: dazed and confused.