The special playback function (NEW MONO mode) can only be used for music files that have been saved on your device under the following conditions:

• The song has been synchronized with the device in iTunes (e.g., the file was imported from a CD)
• The song was purchased on the iTunes Store, and was downloaded using the standard Music app on iOS
• You are using iTunes Match and the song has been synchronized through the iCloud Music Library

Notice

• When you are using Apple Music and the iCloud Music Library is on, DRM will be applied to music files synchronized through the cloud. Consequently, tracks that even meet the above requirements may not be played in the NEW MONO mode (this does not apply in instances where the iTunes Match is used simultaneously). Please download or synchronize music files to your device while the iCloud Music Library is disabled.
• NEW MONO mode cannot be performed on songs provided through Apple Music or that are only saved on the cloud.

When the icon is displayed in the album or player screen, the song is being hosted by a streaming service (e.g., Apple Music) or is only saved on the Cloud. These songs will not undergo the special conversion, and will continue to play normally.