Problem with duplicity while verifying backup

DUPLICITY: . Found primary backup chain with matching signature chain:
DUPLICITY: . -------------------------
DUPLICITY: . Chain start time: Fri Mar 13 09:56:57 2015
DUPLICITY: . Chain end time: Fri Jun 5 11:04:57 2015
DUPLICITY: . Number of contained backup sets: 6
DUPLICITY: . Total number of contained volumes: 1028
DUPLICITY: . Type of backup set: Time: Num volumes:
DUPLICITY: . Full Fri Mar 13 09:56:57 2015 826
DUPLICITY: . Incremental Fri May 29 07:17:30 2015 191
DUPLICITY: . Incremental Tue Jun 2 08:37:28 2015 5
DUPLICITY: . Incremental Thu Jun 4 07:22:58 2015 3
DUPLICITY: . Incremental Fri Jun 5 07:12:41 2015 2
DUPLICITY: . Incremental Fri Jun 5 11:04:57 2015 1
DUPLICITY: . -------------------------
DUPLICITY: . No orphaned or incomplete backup sets found.

DUPLICITY: DEBUG 1
DUPLICITY: . Releasing lockfile <lockfile.LinkFileLock instance at 0x7f96059a1170>

DUPLICITY: DEBUG 1
DUPLICITY: . Removing still remembered temporary file /tmp/duplicity-Rj39O1-tempdir/mkstemp-Q9Q6Dn-1

DUPLICITY: ERROR 30 KeyError
DUPLICITY: . Traceback (most recent call last):
DUPLICITY: . File "/usr/bin/duplicity", line 1523, in <module>
DUPLICITY: . with_tempdir(main)
DUPLICITY: . File "/usr/bin/duplicity", line 1517, in with_tempdir
DUPLICITY: . fn()
DUPLICITY: . File "/usr/bin/duplicity", line 1371, in main
DUPLICITY: . do_backup(action)
DUPLICITY: . File "/usr/bin/duplicity", line 1448, in do_backup
DUPLICITY: . restore(col_stats)
DUPLICITY: . File "/usr/bin/duplicity", line 716, in restore
DUPLICITY: . restore_get_patched_rop_iter(col_stats)):
DUPLICITY: . File "/usr/lib/python2.7/dist-packages/duplicity/patchdir.py", line 553, in Write_ROPaths
DUPLICITY: . for ropath in rop_iter:
DUPLICITY: . File "/usr/lib/python2.7/dist-packages/duplicity/patchdir.py", line 516, in integrate_patch_iters
DUPLICITY: . for patch_seq in collated:
DUPLICITY: . File "/usr/lib/python2.7/dist-packages/duplicity/patchdir.py", line 388, in yield_tuples
DUPLICITY: . setrorps(overflow, elems)
DUPLICITY: . File "/usr/lib/python2.7/dist-packages/duplicity/patchdir.py", line 377, in setrorps
DUPLICITY: . elems[i] = iter_list[i].next()
DUPLICITY: . File "/usr/lib/python2.7/dist-packages/duplicity/patchdir.py", line 106, in filter_path_iter
DUPLICITY: . for path in path_iter:
DUPLICITY: . File "/usr/lib/python2.7/dist-packages/duplicity/patchdir.py", line 120, in difftar2path_iter
DUPLICITY: . tarinfo_list = [tar_iter.next()]
DUPLICITY: . File "/usr/lib/python2.7/dist-packages/duplicity/patchdir.py", line 338, in next
DUPLICITY: . self.set_tarfile()
DUPLICITY: . File "/usr/lib/python2.7/dist-packages/duplicity/patchdir.py", line 332, in set_tarfile
DUPLICITY: . self.current_fp = self.fileobj_iter.next()
DUPLICITY: . File "/usr/bin/duplicity", line 752, in get_fileobj_iter
DUPLICITY: . backup_set.volume_name_dict[vol_num],
DUPLICITY: . KeyError: 34
DUPLICITY: .

Versions:

Ubuntu: 15.04
duplicity 0.7.02+bzr1092