diff --git a/picard/puidmanager.py b/picard/puidmanager.py
index 910c18642..85a86b1e6 100644
--- a/picard/puidmanager.py
+++ b/picard/puidmanager.py
@@ -30,13 +30,13 @@ class PUIDManager(QtCore.QObject):
     def add(self, puid, trackid):
         """Add a PUID to the manager."""
         if puid:
-            self.__puids[puid] = [trackid, trackid]
+            self.__puids[puid] = (trackid, trackid)
             self.__check_unsubmitted()
 
     def update(self, puid, trackid):
         """Update the PUID."""
         if puid:
-            self.__puids[puid][1] = trackid
+            self.__puids[puid] = (self.__puids.get(puid, (None, None))[0], trackid)
             self.__check_unsubmitted()
 
     def __unsubmitted(self):
@@ -66,7 +66,7 @@ class PUIDManager(QtCore.QObject):
             self.tagger.window.set_statusbar_message(N_('PUIDs successfully submitted!'), timeout=3000)
             for puid in puids.values():
                 try:
-                    self.__puids[puid][1] = self.__puids[puid][0]
+                    self.__puids[puid] = (self.__puids[puid][0], self.__puids[puid][0])
                 except KeyError:
                     pass
             self.__check_unsubmitted()
diff --git a/picard/tagger.py b/picard/tagger.py
index ebaa69923..5492024c5 100644
--- a/picard/tagger.py
+++ b/picard/tagger.py
@@ -311,8 +311,7 @@ class Tagger(QtGui.QApplication):
         puid = file.metadata['musicip_puid']
         trackid = file.metadata['musicbrainz_trackid']
         albumid = file.metadata['musicbrainz_albumid']
-        if puid and trackid:
-            self.puidmanager.add(puid, trackid)
+        self.puidmanager.add(puid, trackid)
         if albumid:
             if trackid:
                 self.move_file_to_album(file, albumid)
@@ -590,16 +589,16 @@ class Tagger(QtGui.QApplication):
         self.log.debug("Clustering %r", objs)
         if len(objs) <= 1:
             objs = [self.unmatched_files]
+        fcmp = lambda a, b: (
+            cmp(a.discnumber, b.discnumber) or
+            cmp(a.tracknumber, b.tracknumber) or
+            cmp(a.base_filename, b.base_filename))
         files = self.get_files_from_objects(objs)
         for name, artist, files in Cluster.cluster(files, 1.0):
             QtCore.QCoreApplication.processEvents()
             cluster = Cluster(name, artist)
             self.clusters.append(cluster)
             self.emit(QtCore.SIGNAL("cluster_added"), cluster)
-            fcmp = lambda a, b: (
-                cmp(a.discnumber, b.discnumber) or
-                cmp(a.tracknumber, b.tracknumber) or
-                cmp(a.base_filename, b.base_filename))
             for file in sorted(files, fcmp):
                 file.move(cluster)