Set AVCaptureSession output to BlackHole or another arbitrary device by an output device name

BlackHoleAVCaptureAudioPreviewOutput.swift

    private let audioOutput: AVCaptureAudioPreviewOutput = {
        let audioOutput = AVCaptureAudioPreviewOutput()
        audioOutput.volume = UserDefaults.standard.volume

        struct Device {
            var name: String?
            var uid: String?
        }
        var devicesProperty = AudioObjectPropertyAddress(mSelector: kAudioHardwarePropertyDevices, mScope: kAudioDevicePropertyScopeOutput, mElement: kAudioObjectPropertyElementWildcard)
        var devicesSize: UInt32 = 0
        AudioObjectGetPropertyDataSize(AudioObjectID(kAudioObjectSystemObject), &devicesProperty, 0, nil, &devicesSize)
        let devicesResult = UnsafeMutablePointer<AudioDeviceID>.allocate(capacity: Int(devicesSize))
        AudioObjectGetPropertyData(AudioObjectID(kAudioObjectSystemObject), &devicesProperty, 0, nil, &devicesSize, devicesResult)
        let deviceIDs = UnsafeBufferPointer(start: devicesResult, count: Int(devicesSize))
        let devices = deviceIDs.map { deviceID -> Device in
            var nameProperty = AudioObjectPropertyAddress(mSelector: kAudioDevicePropertyDeviceNameCFString, mScope: kAudioDevicePropertyScopeOutput, mElement: kAudioObjectPropertyElementWildcard)
            var uidProperty = AudioObjectPropertyAddress(mSelector: kAudioDevicePropertyDeviceUID, mScope: kAudioDevicePropertyScopeOutput, mElement: kAudioObjectPropertyElementWildcard)
            var size: UInt32 = UInt32(MemoryLayout<CFString>.size)
            var name: CFString?
            var uid: CFString?
            AudioObjectGetPropertyData(deviceID, &nameProperty, 0, nil, &size, &name)
            AudioObjectGetPropertyData(deviceID, &uidProperty, 0, nil, &size, &uid)
            return Device(name: name as String?, uid: uid as String?)
        }
        NSLog("%@", "\(devices)")
        audioOutput.outputDeviceUniqueID = devices.first {$0.name == "BlackHole 16ch"}?.uid

        return audioOutput
    }()