System.unloadplugin(uint handle) not working

FMOD Engine
1

Hi,

I’m creating a dsp using the system.loadplugin() (it is a .dll VST2 plugin)
I call after that createDSPPlugin().
Everything is working as expected.

When i call the system.unloadPlugin() it seems it does not unload it. I mean FMOD returns FMOD.RESULTS.OK but i can still access the handle with an external tool that communicates with the VST.

Is this a bug ?
Is there any other options to destroy a plugin handle ?

2

I need help ! It make crash the Unity Editor and my software because i need to destroy an recreate my FMOD system and reload the vst plugin. By doing that it spaw one instance of the vst each time i destroy and recreate the FMOD system !

I need to destroy the FMOD system because I need to go from RAW mode to automatic mode to be able to use 3d sounds positionning…

3

What version of FMOD are you using?

If you try to access the handle, through FMOD, after it has been unload you should get FMOD_ERR_PLUGIN_MISSING.

4

Hi Cameron !
I’m using FMOD Studio 2.00.04

when i destroy the System here is the code i execute before :

        if (0 != Handle)
        {
            FMOD.RESULT result;
            do
            {
                CoreSystem.update();
                result = CoreSystem.unloadPlugin(Handle);
            } while (result == FMOD.RESULT.ERR_DSP_INUSE);
        }
        else 
            Debug.LogWarning("No handle so no need to clean it !");
        FMOD.RESULT test = CoreSystem.createDSPByPlugin(Handle, out FMOD.DSP dsp);
        Debug.LogError(test);

The last Debug.LogError says exactly what you expectec : FMOD_ERR_PLUGIN_MISSING .

5

That is expected. What is the issue?

6

Hi Cameron,

The issue is that the instance of the VST seams to continue to be active some how.
Any way i try to find a workaround.
Now i need to destroy it because i need to reset FMOD (destroy and create system again) to detect output changes. I’m trying to avoid to reset FMOD completly. This is the only part where i’ve not found a solution.

i’ve implemented the callbacks for that. It return all the time a FMOD.SYSTEM_CALLBACK_TYPE.RECORDLISTCHANGED but not very often the FMOD.SYSTEM_CALLBACK_TYPE.DEVICELISTCHANGED…

it seams that the recordlistchanged trigger because of the loopback of the outputs… and i need to detect both changes.

Is there a way to make FMOD detect DeviceListChanged and the Driver order to reset (to use with System.SetDriver()) ?

[AOT.MonoPInvokeCallback(typeof(FMOD.SYSTEM_CALLBACK))]
static FMOD.RESULT DevicesChangedCallback(IntPtr system, FMOD.SYSTEM_CALLBACK_TYPE type, IntPtr commanddata1, IntPtr commanddata2, IntPtr userdata)
        {
            lock (callback_lock)
            {
                if (userdata != IntPtr.Zero)
                {
                    Debug.Log($"FMOD Devices has Changed {type}");
                    GCHandle objecthandle = GCHandle.FromIntPtr(userdata);
                    var manager = (objecthandle.Target as FMODCallBacksParameters);

                    switch (type)
                    {
                        case FMOD.SYSTEM_CALLBACK_TYPE.DEVICELISTCHANGED:
                            manager.HS_OutputDevicesChanged = true;
                            break;
                        case FMOD.SYSTEM_CALLBACK_TYPE.RECORDLISTCHANGED:
                            manager.HS_InputDevicesChanged = true;
                            break;
                    }
                }
            }

            return FMOD.RESULT.OK;
        }

FInally, i’ve found a workaround. The callbacks seams not working properly.
Here is my solution to run in the FixedUpdate() in Unity :

public static bool CheckOutputListChange()
        {
            result = FMODLowLevelSystems[ECanal.Canal1].getNumDrivers(out int NumDrivers);
            ERRCHECK(result, instance.name);
            if (instance.DevicesName.Count == NumDrivers || !isFMODInit) return false;
            else return true;
        }
public static bool CheckInputListChange()
                {
                    result = FMODLowLevelSystems[ECanal.Canal1].getRecordNumDrivers(out _, out int NumConnected);
                    ERRCHECK(result, instance.name);
                    if (instance.RecordDevicesName.Count == NumConnected || !isFMODInit) return false;
                    else return true;
                }
7

If you were to try to release a plugin while it is in use you will get an error (FMOD_ERR_DSP_INUSE), and if you try to use a plugin after it has been released you will get (FMOD_ERR_PLUGIN_MISSING). I’m not sure how it is still active. Are you able to send us a project that reproduces this?

FMOD.SYSTEM_CALLBACK_TYPE.DEVICELISTCHANGED should be doing this, otherwise that could be a bug.

Using FMOD_SYSTEM_CALLBACK_DEVICELISTCHANGED (Windows only) will disable any automated device ejection/insertion handling. Use this callback to control the behavior yourself.