public static float?GetSystemSoundsVolume()
        {
            Interfaces.ISimpleAudioVolume volume = GetSystemSoundsVolumeObject();
            if (volume == null)
            {
                throw new Exception("No session found for system sounds");
            }

            float level;

            volume.GetMasterVolume(out level);
            Marshal.ReleaseComObject(volume);
            return(level * 100);
        }
        public static float?GetApplicationVolume(int pid)
        {
            Interfaces.ISimpleAudioVolume volume = GetVolumeObject(pid);
            if (volume == null)
            {
                throw new Exception("No application found for pid");
            }

            float level;

            volume.GetMasterVolume(out level);
            Marshal.ReleaseComObject(volume);
            return(level * 100);
        }