Timeout on a really fast query

Hello IdeaBlade,
I'm currently facing troubles when executing a simple stored procedure that executing from SQLServer manager returns in 1-2 second...calling it from my WPF applicazion takes a lot of time and it goes in timeout (other stored procedure that takes 20-40 seconds run fine)

my call is :

    public void LoadData()
        {
            IsBusy = true;
            CanPrintExport = false;

            _repository.LoadNote(App.LoggedUser.IDIstituto, Date,
                           results =>
                           {
                               ResultList = new BindableCollection<NotesResult>(results.Cast<NotesResult>());

                               CanPrintExport = true;
                               IsBusy = false;
                           },
                                      e => MessageBox.Show(e.Message));

        }

and here's my call to the stored procesure in applicationrepository

   public INotifyCompleted LoadNote(int idIstituto, DateTime date, Action<IEnumerable> onSuccess, Action<Exception> onFail)
        {
            var query = Manager.myStore(idIstituto, date);

            query.CommandTimeout = 60; //this can be 180 ...always got the same problem
          
            var op = query.ExecuteAsync();

            return op.OnComplete(onSuccess, onFail);
        }

The strange thing is that a lot of time elapse between the load button click and the RPC completed on the Sql Server profile to appear..

Thanks
Paolo