diff --git a/src/calibre/devices/prs505/driver.py b/src/calibre/devices/prs505/driver.py
index 846ca9593d..794bf66600 100644
--- a/src/calibre/devices/prs505/driver.py
+++ b/src/calibre/devices/prs505/driver.py
@@ -96,7 +96,8 @@ class PRS505(USBMS):
         c = self.initialize_XML_cache()
         blists = {}
         for i in c.paths:
-            blists[i] = booklists[i]
+            if booklists[i] is not None:
+                blists[i] = booklists[i]
         opts = self.settings()
         collections = ['series', 'tags']
         if opts.extra_customization:
diff --git a/src/calibre/devices/prs505/sony_cache.py b/src/calibre/devices/prs505/sony_cache.py
index 5b11b89a0a..61ae610c26 100644
--- a/src/calibre/devices/prs505/sony_cache.py
+++ b/src/calibre/devices/prs505/sony_cache.py
@@ -137,6 +137,7 @@ class XMLCache(object):
         self.ensure_unique_playlist_titles()
         self.prune_empty_playlists()
         for i, root in self.record_roots.items():
+            ans[i] = {}
             for playlist in root.xpath('//*[local-name()="playlist"]'):
                 items = []
                 for item in playlist:
@@ -153,7 +154,7 @@ class XMLCache(object):
         for playlist in root.xpath('//*[local-name()="playlist"]'):
             if playlist.get('title', None) == title:
                 return playlist
-        ans = root.makelement('{%s}playlist'%self.namespaces[bl_idx],
+        ans = root.makeelement('{%s}playlist'%self.namespaces[bl_idx],
                 nsmap=root.nsmap, attrib={
                     'uuid' : uuid(),
                     'title': title,
@@ -286,7 +287,7 @@ class XMLCache(object):
                 record = self.book_by_lpath(book.lpath, root)
                 if record is None:
                     record = self.create_text_record(root, i, book.lpath)
-                self.update_record(record, book, path, i)
+                self.update_text_record(record, book, path, i)
                 bl_pmap = playlist_map[i]
                 self.update_playlists(i, root, booklist, bl_pmap,
                         collections_attributes)
@@ -300,8 +301,8 @@ class XMLCache(object):
     def update_playlists(self, bl_index, root, booklist, playlist_map,
             collections_attributes):
         collections = booklist.get_collections(collections_attributes)
-        for category, books in collections:
-            records = [self.book_by_lpath(b.lpath) for b in books]
+        for category, books in collections.items():
+            records = [self.book_by_lpath(b.lpath, root) for b in books]
             # Remove any books that were not found, although this
             # *should* never happen
             if DEBUG and None in records:
@@ -357,7 +358,7 @@ class XMLCache(object):
         timestamp = getattr(os.path, 'get'+timestamp)(path)
         date = strftime(timestamp)
         record.set('date', date)
-        record.set('size', os.stat(path).st_size)
+        record.set('size', str(os.stat(path).st_size))
         record.set('title', book.title)
         record.set('author', authors_to_string(book.authors))
         ext = os.path.splitext(path)[1]
diff --git a/src/calibre/devices/usbms/driver.py b/src/calibre/devices/usbms/driver.py
index 7b3531abf6..76996481a5 100644
--- a/src/calibre/devices/usbms/driver.py
+++ b/src/calibre/devices/usbms/driver.py
@@ -98,11 +98,10 @@ class USBMS(CLI, Device):
                     import traceback
                     traceback.print_exc()
             return changed
-
         if isinstance(ebook_dirs, basestring):
             ebook_dirs = [ebook_dirs]
         for ebook_dir in ebook_dirs:
-            ebook_dir = self.path_to_unicode(filesystem_encoding)
+            ebook_dir = self.path_to_unicode(ebook_dir)
             ebook_dir = self.normalize_path( \
                             os.path.join(prefix, *(ebook_dir.split('/'))) \
                                     if ebook_dir else prefix)