「Play song list screen"The songs display becoming gray are the following two cases.

1. Light gray
   「Player screen"The shows that skipping playback playback mode display is Skip play the play tempo range is outside the range of the original tempo when the current settings in the song. Tap the playback mode display change to Adjust play, tap tempo option button to change the tempo specified that, to play.

2. Dark gray
   Dark gray presents 'NA' tempo display column is Walking Player does not play songs.Mostly DRM(Copyright protection)And this dark gray with songs cannot be played. You can play a song with DRM is app music player or standard, or standard music player Apple internal use only. For walking Player to directly loading music data and analysis required apps load songs with DRM data cannot be played.

   But fortunately Apple is ahead in direction to eliminate this DRM.Songs imported from CDs will not grant the DRM so you can play without problems. Also, all purchased from Japan iTunesStore 3/2012 songs are DRM is not granted(The United States is more DRM-free from the previous)。 Please note that songs purchased from Japan iTunesStore 2/2012 a given DRM is.

   The DRM gives songs you can deselect either of the following DRM in a way.

• Using a computer with iTunes once writes CD-r, and then re-imported from the CD-r.
• Download and register to iTunes Match the previously purchased music in the iTunes Plus format.
  (Reference:iTunes Store：iTunes Plus for common questions (FAQ))

* However, 8/2013 current, iTunesStore Japan iTunes Match registration cannot. The latter is in Japan is another must wait a while.