MacOS14 system modifies CMSampleBuffer transparency

In MacOS14 system, the transparency of CMSampleBuffer is 0. Why after sending through the send function of CMIOExtensionStream, the receiving end uses AVCaptureSession to addOutput: AVCaptureVideoDataOutput object, AVCaptureVideoDataOutput sets videoSettings to kCVPixelBufferPixelFormatTypeKey: @(kCVPixelFormatType_32BGRA), the receiving end's receiving delegate method - (void)captureOutput:( AVCaptureOutput *)output didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection The transparency of the sampleBuffer returned is actually 255. The correct sampleBuffer transparency of the MacOS13 system is 0. In this case, how can I return the same as the 13 system? What needs to be set? Attribute?