Question

I’m getting that exception when I try to run a simple DirectSound program. Here’s the code:

using System;
using System.Runtime.InteropServices;
using System.Threading;
using Microsoft.DirectX.DirectSound;

namespace AudioDemo
{
    class Program
    {
        [DllImport("user32.dll")]
        private static extern IntPtr GetDesktopWindow();

        static void Main(string[] args)
        {
            // output device

            var device = new Device();
            device.SetCooperativeLevel(GetDesktopWindow(), CooperativeLevel.Normal);

            // format description

            var format = new WaveFormat
            {
                BitsPerSample = 8,
                Channels = 1,
                FormatTag = WaveFormatTag.Pcm,
                SamplesPerSecond = 8000
            };

            format.BlockAlign = (short)(format.BitsPerSample / 8 * format.Channels);
            format.AverageBytesPerSecond = format.SamplesPerSecond * format.BlockAlign;

            var outputLatency = 20;
            var frameSize = format.AverageBytesPerSecond * outputLatency / 1000;

            // buffer 

            var description = new BufferDescription
            {
                BufferBytes = frameSize,
                Format = format,
                DeferLocation = true,
                GlobalFocus = true
            };

            var outputBuffer = new SecondaryBuffer(description, device);

            // buffer notifications

            var notify = new Notify(outputBuffer);

            // ...
        }
    }
}

I get the exception on the last line (var notify = new Notify(outputBuffer);).

Not sure what went wrong. The buffer was initialized correctly.

Answer 1

It’s not clear to me what you’re trying to do with your outputLatency and frameSize variables, or with the BufferBytes property, but my guess is there is where your problem is.