mciSendString working only on main Thread?

[mikker_123]

Hi, I was just wondering if anybody else has same problem -> I can't seem to get this to work on other than UI thread. So this works if you call it directly on form

    \[DllImport("winmm.dll")\]
    private static extern long mciSendString(string strCommand,
        string strReturn, int iReturnLength, IntPtr hwndCallback);

private void OnSomeButtonClick()
{
PlaySound(new object[] {"c:/sound.mp3", this.Handle});
}

    private void PlaySound(object soundToPlay)
    {
        string soundToPlay = ((object\[\])data)\[0\];
        Handle handle = ((object\[\])data)\[1\];

        string sCommand = "open \\"" + soundToPlay + "\\" type mpegvideo alias MediaFile";
        mciSendString(sCommand, null, 0, IntPtr.Zero);

        sCommand = "play MediaFile wait";
        mciSendString(sCommand, null, 0, handle);

        string sCommand = "close MediaFile";
        mciSendString(sCommand, null, 0, IntPtr.Zero);
    }

But if you say:

private void OnSomeButtonClick()
{
ThreadPool.QueueUserWorkItem(new WaitCallback(PlaySound), new object[] {"c:/sound.mp3", this.Handle});
}

It won't play sound... anyone? Tnx in advance