ImoduleConfig in C# giving acess violation error

[ComImport, SuppressUnmanagedCodeSecurity, Guid("486F726E-4D43-49B9-8A0C-C22A2B0524E8"),
     InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
    public interface IModuleConfig : IPersistStream
    {

        new void GetClassID([Out] out Guid pClassID);
        [PreserveSig]
        int SetValue([In, MarshalAs(UnmanagedType.LPStruct)] Guid pParamID, [In]ref Object pValue);

        [PreserveSig]
        int GetValue([In, MarshalAs(UnmanagedType.LPStruct)] Guid pParamID, ref Object pValue);

        [PreserveSig]
        int GetParamConfig([In, MarshalAs(UnmanagedType.LPStruct)] Guid pParamID, out IParamConfig pValue);

        [PreserveSig]
        [return: MarshalAs(UnmanagedType.U1)]
        bool IsSupported([In, MarshalAs(UnmanagedType.LPStruct)] Guid pParamID);

        [PreserveSig]
        int SetDefState();

        [PreserveSig]
        int EnumParamsint(ref long pNumParams, ref Guid pParamIDs);

        [PreserveSig]
        int CommitChanges([Out] out Object pReason);

        [PreserveSig]

        int DeclineChanges();

        [PreserveSig]
        void SaveToRegistry(
    [In] Int32 hKeyRoot,
    [In, MarshalAs(UnmanagedType.BStr)] String pszKeyName,
    [In, MarshalAs(UnmanagedType.Bool)] bool bPreferReadable);

        [PreserveSig]

        void LoadFromRegistry(
            [In] Int32 hKeyRoot,
            [In, MarshalAs(UnmanagedType.BStr)] String pszKeyName,
            [In, MarshalAs(UnmanagedType.Bool)] bool bPreferReadable);


        [PreserveSig]


        int RegisterForNotifies([In, MarshalAs(UnmanagedType.Interface)] ref IModuleConfig pModuleCallback);

        [PreserveSig]

        int UnregisterFromNotifies([In, MarshalAs(UnmanagedType.Interface)] ref IModuleConfig pModuleCallback);

    }


When calling the ComitChanges method I'm getting AcessViolation exception.

object obj2 = new object();
hr = pNetworkSourceModuleConfig.CommitChanges(out obj2);