not sure if its a problem with my itunes, or my music specifically but this is strange

in itunes, if i click on music it lists 17,197 songs
in itunes if i click on my ipod it says i have 17,183

on my ipod settings > about says 17,183
if i highlight shuffle songs it says 17,183
but if i highlight music, it says 16,997

anyone else ran into this? i'm sure its just duplicates and whatnot, only bothers me because i have a mild case of OCD