Rekordbox adding the wrong songs (glitch)

Hey guys interesting glitch with two different types:

Via iTunes link tracks in playlists all fine as meant to be, sync to thumbdrive and track remains labelled as it should be but plays a completely different song.  Remove song from iTunes, readd, delete playlist off thumbdrive resync, same issue.

Other glitch does the same thing but just adds another song instead of the one that's meant to be there.  Anyone come across this?

After the weekend gigs I'll give the thumbdrive a full reformat and see what that does but completely stumped how to work around the glitch.