Error in FFT, when the TS sampling step is big

2017-11-02 08:35:12,534 - ERROR [proc:26627]  - tvb.core.operation_async_launcher - Could not execute operation 27
2017-11-02 08:35:12,534 - ERROR [proc:26627]  - tvb.core.operation_async_launcher - slice indices must be integers or None or have an __index__ method
Traceback (most recent call last):
  File "/WORK/TVB/tvb-root/framework_tvb/tvb/core/operation_async_launcher.py", line 80, in do_operation_launch
    OperationService().initiate_prelaunch(curent_operation, adapter_instance, {}, **PARAMS)
  File "/WORK/TVB/tvb-root/framework_tvb/tvb/core/services/operation_service.py", line 355, in initiate_prelaunch
    self._handle_exception(excep1, temp_files, msg, operation)
  File "/WORK/TVB/tvb-root/framework_tvb/tvb/core/services/operation_service.py", line 333, in initiate_prelaunch
    result_msg, nr_datatypes = adapter_instance._prelaunch(operation, unique_id, available_space, **params)
  File "/WORK/TVB/tvb-root/framework_tvb/tvb/core/adapters/abcadapter.py", line 89, in new_function
    return func(*args, **kw)
  File "/WORK/TVB/tvb-root/framework_tvb/tvb/core/adapters/abcadapter.py", line 318, in _prelaunch
    result = self.launch(**kwargs)
  File "/WORK/TVB/tvb-root/framework_tvb/tvb/adapters/analyzers/fourier_adapter.py", line 174, in launch
    partial_result = self.algorithm.evaluate()
  File "/WORK/TVB/tvb-root/scientific_library/tvb/analyzers/fft.py", line 119, in evaluate
    for start in starts]
TypeError: slice indices must be integers or None or have an __index__ method