diff --git a/oml/library.py b/oml/library.py
index eee921e..d840872 100644
--- a/oml/library.py
+++ b/oml/library.py
@@ -377,6 +377,10 @@ def sync_db():
     from sqlalchemy.orm import load_only
     import item.models
     first = True
+    missing_previews = []
+    state.sync_db = True
+
+    #FIXME: why is this loop needed
     with db.session():
         sort_ids = {i.item_id for i in item.models.Sort.query.options(load_only('item_id'))}
         if sort_ids:
@@ -387,9 +391,11 @@ def sync_db():
                     if first:
                         first = False
                         logger.debug('sync items')
-                    i.update(commit=False)
-                    if i.info.get('mediastate') == 'unavailable' and state.tasks:
-                        state.tasks.queue('getpreview', i.id)
+                    #why?
+                    #i.update(commit=False)
+                    i.update_sort(commit=False)
+                    if i.info.get('mediastate') == 'unavailable':
+                        missing_previews.append(i.id)
                     commit = True
                     #logger.debug('sync:%s', i)
                     t0 = maybe_commit(t0)
@@ -397,6 +403,7 @@ def sync_db():
                     break
             if commit:
                 state.db.session.commit()
+
     if not first:
         logger.debug('synced items')
     if not state.shutdown:
@@ -408,6 +415,12 @@ def sync_db():
     item.models.Sort.query.filter_by(item_id=None).delete()
     item.models.Find.query.filter_by(item_id=None).delete()
 
+    if missing_previews and state.tasks:
+        logger.debug('queueing download of %s missing previews', len(missing_previews))
+        for id in missing_previews:
+            state.tasks.queue('getpreview', id)
+    state.sync_db = False
+
 def cleanup_lists():
     import item.models
     import user.models
diff --git a/oml/nodes.py b/oml/nodes.py
index 27d7658..85ee9b7 100644
--- a/oml/nodes.py
+++ b/oml/nodes.py
@@ -598,6 +598,8 @@ class Nodes(Thread):
     def _pull(self):
         if not state.sync_enabled or settings.preferences.get('downloadRate') == 0:
             return
+        if state.sync_db:
+            return
         if state.activity and state.activity.get('activity') == 'import':
             return
         self._pulling = True
diff --git a/oml/state.py b/oml/state.py
index cc1e804..4dbf2da 100644
--- a/oml/state.py
+++ b/oml/state.py
@@ -16,6 +16,7 @@ websockets = []
 uisockets = []
 peers = {}
 changelog_size = None
+sync_db = False
 
 activity = {}
 removepeer = {}