NAudio and DirectSound issue with calling Read method

Question

I have a MoveTo method which moves a cursor in my own WaveProvider class. I implemented a Phase Vocoder in this class, so when I move a cursor I need to recreate some objects with new values. There is no problem with WaveOut, but when I use DirectSound, it throws ArgumentNullException.
The problem is that, when program is in MoveTo method, and is changing some values inside object, DirectSound is inside Read method and it makes a crash. I tried to lock WaveProvider during changing position, but DirectSound still can get in Read method.
How to fix it?

Answer 1

What are you locking on? You need to create a lock object inside your WaveProvider and lock on that during both your MoveTo and Read methods:

class MyWaveProvider : IWaveProvider
{
    private object lockObject = new Object();

    public void MoveTo(int pos)
    {
        lock(lockObject)
        {
            // perform the move
        }
    }


    public int Read(byte[] buffer, int offset, int count)
    {
        lock(lockObject)
        {
            // perform the read
        }
    }
}