I tested your code on my machine (also with a mounted mp3 directory :) and had the same problem. When I stepped through with the debugger, I saw that File::Find was getting 1 for nlink instead of 2, so I tried setting $File::Find::dont_use_nlink = 1;
as suggested in File::Find for AFS, and the script worked. (Also I fixed the capitalization of $File::Find::name.) Enjoy!