当默认模式兼容所有类别时，AVAudioSession 中其他模式的用途是什么？

Question

// Access the shared, singleton audio session instance
let session = AVAudioSession.sharedInstance()
do {
    // Configure the audio session for movie playback
    try session.setCategory(AVAudioSessionCategoryPlayback,
                            mode: AVAudioSessionModeMoviePlayback,
                            options: [])
} catch let error as NSError {
    print("Failed to set the audio session category and mode: \(error.localizedDescription)")
}

无法理解音频会话中模式的使用。

modes here

Answer 1

其他模式针对特定用途进行了优化。 "Compatible" 与 "best." 不同例如，当使用 video chat mode 时：

the device’s tonal equalization is optimized for voice and the set of allowable audio routes is reduced to only those appropriate for video chat.

当默认模式兼容所有类别时，AVAudioSession 中其他模式的用途是什么？

What is the use of other modes in AVAudioSession, when default mode is compatible for all categories?

avfoundation

avaudiosession

swift