I have used auriotouch codes in my app and when i record the audio, it shows the audio waves. So, while recording the sound, the mic recognizes the audio input and then the waves would act accordingly to whatever the sound the mic receives. So far its fine. But now, when I click on the play button to play the sound I just recorded, the mic's input should be off, so that the waves would act only according to the audio I recorded before and the waves should not act even if I speak while it plays the previously recorded audio.
So, its more or like muting the mic's input to avoid the recognition of external audio and recognizing only the internal audio of the device.
How this can be done?
You'll find a short tutorial here on reading and playing audio here as well as some links to Apple's documentation on Audio Units and more sample code.
来源：https://stackoverflow.com/questions/16331327/how-to-mute-the-mics-audio-input-and-recognize-only-the-internal-audio-of-the-d