diff --git a/src/calibre/devices/usbms/books.py b/src/calibre/devices/usbms/books.py
index 7a5e8c49b3..0510d1718d 100644
--- a/src/calibre/devices/usbms/books.py
+++ b/src/calibre/devices/usbms/books.py
@@ -241,7 +241,8 @@ class CollectionsBookList(BookList):
             if y is None:
                 return -1
             if isinstance(x, (unicode, str)):
-                c = strcmp(force_unicode(x), force_unicode(y))
+                c = strcmp(unicode(force_unicode(x)),
+                        unicode(force_unicode(y)))
             else:
                 c = cmp(x, y)
             if c != 0: