iTunes won't play certian songs help!!!!

[imac abuser]

I go into iTunes, and certian albums will play, but others will not. The machine is authorized properly, and all the albums are coming from the same external HD. Any ideas what's going on? Movies play, music videos all play. I tried removing one album, and re adding it to the library, and it's not working.

Help I'm going crazy

 

[kgarner]

Are these songs you bought from the iTunes Store or ripped yourself? If you ripped them, what format are they in?

 

[imac abuser]

They are .m4a and i did rip them

 

[imac abuser]

Figured out the problem. For some reason my External HD messed up I unplugged it plugged it back in restarted iTunes and it's working. What's weird was that the songs that some of the songs on the same HD where working