IOError on backup

[dsoprea]

$ bakthat backup images
Backing up images
Password (blank to disable encryption): 
Compressing...
Traceback (most recent call last):
  File "/usr/local/bin/bakthat", line 9, in <module>
    load_entry_point('bakthat==0.6.0', 'console_scripts', 'bakthat')()
  File "/usr/local/lib/python2.7/dist-packages/bakthat/__init__.py", line 649, in main
    app.run()
  File "/usr/local/lib/python2.7/dist-packages/aaargh/app.py", line 176, in run
    return func(**kwargs)
  File "/usr/local/lib/python2.7/dist-packages/bakthat/__init__.py", line 324, in backup
    tar.add(filename, arcname=arcname, exclude=_exclude)
  File "/usr/lib/python2.7/tarfile.py", line 2002, in add
    recursive, exclude, filter)
  File "/usr/lib/python2.7/tarfile.py", line 1995, in add
    self.addfile(tarinfo, f)
  File "/usr/lib/python2.7/tarfile.py", line 2024, in addfile
    copyfileobj(fileobj, self.fileobj, tarinfo.size)
  File "/usr/lib/python2.7/tarfile.py", line 277, in copyfileobj
    buf = src.read(remainder)
IOError: [Errno 5] Input/output error