能够在模拟器上播放Stereo Type Audio，但不能使用示例RemoteIO / AudioUnit应用程序在设备上播放

Question

在这个示例应用程序中，我能够加载立体声数据文件并使用模拟器播放它。但它不适用于该设备。我尝试使用声音编辑器并将立体声剪辑转换为单声道并更改描述符设置，它将仅使用单声道。我很难找到原因，我猜这与我的描述符配置问题有关。

此示例应用位于https://github.com/peter7777usa/TestAudio

PlayBack功能

static OSStatus playbackCallback(void *inRefCon,
                                 AudioUnitRenderActionFlags *ioActionFlags,
                                 const AudioTimeStamp *inTimeStamp,
                                 UInt32 inBusNumber,
                                 UInt32 inNumberFrames,
                                 AudioBufferList *ioData) {
    // Notes: ioData contains buffers (may be more than one!)
    // Fill them up as much as you can. Remember to set the size value in each buffer to match how
    // much data is in the buffer.
    NSLog(@"muffers %d", ioData->mNumberBuffers);
    UInt32 size = 2048;
    if (iosAudio->incomingCircularBuffer.fillCount>size){
        NSLog(@"Playing %d", iosAudio->incomingCircularBuffer.fillCount);
        iosAudio.pkgtotal -=2;
        int32_t availableBytes;
        SInt16 *databuffer = TPCircularBufferTail(&iosAudio->incomingCircularBuffer, &availableBytes);
        memcpy(ioData->mBuffers[0].mData, databuffer, size);
        ioData->mBuffers[0].mDataByteSize = size; // indicate how much data we wrote in the buffer
        TPCircularBufferConsume(&iosAudio->incomingCircularBuffer, size);
    }else{
    }

    return noErr;
}

AudioStreamDescription

// Describe format
AudioStreamBasicDescription audioFormat;
bzero(&audioFormat, sizeof(AudioStreamBasicDescription));
UInt32 channelCount = 2;
UInt32 sampleSize = sizeof(UInt16);
audioFormat.mSampleRate         = 44100.00;
audioFormat.mFormatID           = kAudioFormatLinearPCM;
audioFormat.mFormatFlags        = kAudioFormatFlagsCanonical;;
audioFormat.mFramesPerPacket    = 1;
audioFormat.mChannelsPerFrame   = channelCount;
audioFormat.mBitsPerChannel     = sampleSize * 8;
audioFormat.mBytesPerPacket     = sampleSize * channelCount;
audioFormat.mBytesPerFrame      = sampleSize * channelCount;

// Apply format
status = AudioUnitSetProperty(audioUnit,
                              kAudioUnitProperty_StreamFormat,
                              kAudioUnitScope_Output,
                              kInputBus,
                              &audioFormat,
                              sizeof(audioFormat));