Prevent webcam light from illuminating when accessing microphone in Silverlight 4

Question

I'm writing a small audio recorder component in Silverlight 4. It works fine, but I've noticed that when I'm recording audio, the light on my webcam turns on indicating that the camera is active.

While I know that I'm not doing anything insidious with the webcam, my users would have every right to be suspicious. Is it possible to tell Silverlight that I'm only interested in microphone access and not activate the webcam?

FWIW here's how I'm accessing the mic:

private CaptureSource _source = new CaptureSource();
private MemoryAudioSink _sink;  // Inherits from AudioSink. Doesn't do much more 
                                // than store PCM audio stream in memory

private void Record_Click(object sender, RoutedEventArgs e)
{
    if (( CaptureDeviceConfiguration.AllowedDeviceAccess || 
          CaptureDeviceConfiguration.RequestDeviceAccess() ) && 
        _source.State == CaptureState.Stopped)
    {
        _sink = new MemoryAudioSink();
        _sink.CaptureSource = _source;
        _source.Start();
    }
}

Answer 1

This would depend on the webcam driver - Silverlight would have no control over this.

Answer 2

I'm guessing its related to your use of CaptureSource. Microsoft's web site claims that:

Silverlight 4 APIs only use CaptureSource in a video scenario where audio may not be relevant.

Is there a way to get audio without creating your own CaptureSource?