Controlling volume with AVAudioEngine does not work properly

Number:rdar://FB8910493 Date Originated:11/20/2020
Status:Closed Resolved:
Product:iOS Product Version:14.2
Classification:Crash Reproducible:Yes
When using AVAudioEngine to play back audio:
- Changing the mainMixer properties to control volume causes an exception (crash). This is literally how it's documented, so it's really broken.
- Changing the volume property of an AVAudioPlayerNode has no effect on volume.
- The only functioning way to control volume was to wire an AVAudioUnitEQ in and change the globalGain property, which is clearly not the intended approach.

A sample project was supplied.

UPDATE: my error, as I had connected the output of my eq node to the outputNode rather than the mainMixerNode.


You can add a reduntant mixer node and use that.

By recordtronic at Nov. 23, 2020, 8:12 p.m. (reply...)

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