Question

My code is based on this example and a stop function is already implemented, there are functions to uninitialize and stop the audio unit:

    AudioOutputUnitStop(toneUnit);
    AudioUnitUninitialize(toneUnit);
    AudioComponentInstanceDispose(toneUnit);
    toneUnit = nil;

In the example I linked to a pause function is not necessary since there’s only one frequency being played so there’s no difference between pause and stop. In my implementation however, I’m playing a range of different frequencies and I want to be able to pause playback.

Any ideas how this is done?

Answer 1

• fade out (~10ms) the AUs’ output, feed the output silence after the fade
• remember the position you stopped reading your input signal
• reset the AUs before you resume
• resume from the position you recorded above (here, a fade in of the input signal to the AUs would be also be good)