internal static extern AudioManagerError IsStreamOnDevice(AudioStreamPolicyHandle streamInfo, int deviceId, out bool isOn);
internal static extern AudioManagerError GetFocusReacquisition(AudioStreamPolicyHandle streamInfo, out bool enabled);
internal static extern AudioManagerError GetSoundType(AudioStreamPolicyHandle streamInfo, out AudioVolumeType soundType);
internal static extern AudioManagerError ReleaseFocus(AudioStreamPolicyHandle streamInfo, AudioStreamFocusOptions focusMask, AudioStreamBehaviors audioStreamBehavior, string extraInfo);
internal static extern int GetFocusState(AudioStreamPolicyHandle streamInfo, out AudioStreamFocusState stateForPlayback, out AudioStreamFocusState stateForRecording);
internal static extern AudioManagerError ApplyStreamRouting(AudioStreamPolicyHandle streamInfo);
internal static extern AudioManagerError RemoveDeviceForStreamRouting( AudioStreamPolicyHandle streamInfo, int device);
internal static extern AudioManagerError Create(AudioStreamType streamType, FocusStateChangedCallback callback, IntPtr userData, out AudioStreamPolicyHandle streamInfo);
internal static extern AudioManagerError GetPreferredDevice(AudioStreamPolicyHandle streamInfo, out int inDeviceId, out int outDeviceId);
internal static extern AudioManagerError SetPreferredDevice(AudioStreamPolicyHandle streamInfo, AudioDeviceIoDirection direction, int deviceId);