- iOS 5.0–7.0Deprecated
If there is an audio output available, the array usually contains one
CFDictionary object with a single key, namely
k, whose value is one of the constants in Audio Output Routes.
In certain circumstances, such as when a ringtone is being sent to the device speaker and to a connected headset, the array contains more than one dictionary.
If no audio output is available, the array is empty.