PInvoke signature does not match the unmanaged target signature. A call to PInvoke function 'uEyeDotNet!uEye.Tools.Video+ToolsWrapper::InitAviX86'

Question

I am using the uEye API (Dll) to record video from the live camera. I got it working on .NET 6, but for a reason I had to switch to .NET Framework 4.8.1. And now it's throwing this: Managed Debugging Assistant 'PInvokeStackImbalance'.

Full details of the error:

Managed Debugging Assistant 'PInvokeStackImbalance' Message=Managed Debugging Assistant 'PInvokeStackImbalance' : 'A call to PInvoke function 'uEyeDotNet!uEye.Tools.Video+ToolsWrapper::InitAviX86' has unbalanced the stack. This is likely because the managed PInvoke signature does not match the unmanaged target signature. Check that the calling convention and parameters of the PInvoke signature match the target unmanaged signature.'

private void btnRecord_Click(object sender, EventArgs e)
    {
        try
        {
            string filename = DateTime.Now.ToString("yyyy-dd-M--HH-mm-ss") + ".avi";
            camera.Video.Start(procedure_path + "/videos/" + filename);
        }
        catch (Exception)
        {
            throw;
        }
    }

Code from the DLL:

public Status Start(string strFileName)
    {
        Status status = Status.Success;
        if (m_VideoHandle.Init(m_CamParent, out s32VideoID) == Status.Success)
        {
            m_bInitialize = true;
        }

        if (m_bInitialize && !m_bRunning)
        {
            new PixelFormat(m_CamParent).Get(out var mode);
            Memory memory = new Memory(m_CamParent);
            memory.GetActive(out int s32MemId);
            memory.GetSize(s32MemId, out var size);
            status = m_VideoHandle.SetImageSize(s32VideoID, mode & (ColorMode)(-16385), size.Width, size.Height);
            int s32Quality = ((m_s32VideoQuality != 0) ? m_s32VideoQuality : 75);
            m_VideoHandle.SetQuality(s32VideoID, s32Quality);
            status = m_VideoHandle.Open(s32VideoID, strFileName);
            double f64Value = 0.0;
            if (m_f64VideoFrameRate == 0.0)
            {
                new Timing(m_CamParent).Framerate.Get(out f64Value);
            }
            else
            {
                f64Value = m_f64VideoFrameRate;
            }

            status = m_VideoHandle.SetFramerate(s32VideoID, f64Value);
            status = m_VideoHandle.Start(s32VideoID);
            if (status == Status.Success)
            {
                m_CamParent.EventFrame += onSaveFrame;
                m_bRunning = true;
            }
        }
        else
        {
            status = Status.NoSuccess;
        }

        return status;
    }

The DLL import definition:

[DllImport("uEye_tools", CallingConvention = CallingConvention.Cdecl, EntryPoint = "isavi_InitAVI")]
        public unsafe static extern int InitAviX86(int* s32ID, int hCam);

The function:

public unsafe Status Init(Camera camera, out int s32VideoID)
    {
        Status status = Status.Success;
        s32VideoID = 0;
        camera.GetHandle(out var camHandle);
        int num = 0;
        try
        {
            fixed (int* s32ID = &s32VideoID)
            {
                num = ((IntPtr.Size != 4) ? ToolsWrapper.InitAviX64(s32ID, camHandle) : ToolsWrapper.InitAviX86(s32ID, camHandle));
                status = (Status)num;
                if (status == Status.Success)
                {
                    m_bDllFound = true;
                    return status;
                }

                return status;
            }
        }
        catch (DllNotFoundException)
        {
            return Status.NoSuccess;
        }
    }