musics in library can be played properly but when I sync them to the product, it doesn't work

Hi, technical support team!

I have just purchased iPad Mini and this product doesn't know how to stop surprising me with its awesome features.

However, I seem to have an issue, syncing musics to iTunes.

When I check the Music Library, musics are all fine and iTunes can play music very well also.

However, when i try to "Autofill" the music libraries, the titles of the music are color gray. It can't be synced.

"Manually manage music and videos" is already checked. Still, I can't drag and drop to sync music to iPad mini using iTunes, from my document.

I can see the music titles, but it's color gray and it doesn't work.

some says, iTunes has to be updated so I'm gonna try it as soon as possible.

I am also searching other solutions but since iPad mini is quite new, I can't seem to find any help. I'm so desperate so I'm asking for some help here.

I spent my new year finding the solution.

Your help or advise will be very appreciated!

thank you and wish you all luck this new year!