problem with thumb

[luppolo]

hi
i'm a problem for viewing the music folder thumb
but not in the video folder thumb

please help me

here a sample screenshot

problem in music folder PRINCIPAL DIRECTORY

http://www.voltieanime.it/problem in music folder DIR.jpg

no problem into the music folder

http://www.voltieanime.it/no problem into the DIR music folder.jpg

no problem with video folder PRINCIPAL DIRECTORY

http://www.voltieanime.it/no problem with video folder.jpg