Only send news to device if the device supports the format the news has been downloaded in

src/calibre/gui2/library.py

@@ -385,13 +385,35 @@ class BooksModel(QAbstractTableModel):
             metadata.append(mi)
         return metadata
 
+    def get_preferred_formats_from_ids(self, ids, all_formats, mode='r+b'):
+        ans = []
+        for id in ids:
+            format = None
+            fmts = self.db.formats(id, index_is_id=True)
+            if not fmts:
+                fmts = ''
+            available_formats = set(fmts.lower().split(','))
+            for f in all_formats:
+                if f.lower() in available_formats:
+                    format = f.lower()
+                    break
+            if format is None:
+                ans.append(format)
+            else:
+                f = self.db.format(id, format, index_is_id=True, as_file=True, 
+                                   mode=mode)
+                ans.append(f)
+        return ans
+                     
+            
+    
     def get_preferred_formats(self, rows, formats, paths=False):
         ans = []
         for row in (row.row() for row in rows):
             format = None
             fmts = self.db.formats(row)
             if not fmts:
-                return []
+                fmts = ''
             db_formats = set(fmts.lower().split(','))
             available_formats = set([f.lower() for f in formats]) 
             u = available_formats.intersection(db_formats)

src/calibre/gui2/main.py

@@ -887,7 +887,8 @@ class Main(MainWindow, Ui_MainWindow):
         if self.device_connected:
             ids = list(dynamic.get('news_to_be_synced', set([])))
             ids = [id for id in ids if self.library_view.model().db.has_id(id)]
-            files = [self.library_view.model().db.format(id, prefs['output_format'], index_is_id=True, as_file=True) for id in ids]
+            files = self.library_view.model().get_preferred_formats_from_ids(
+                                ids, self.device_manager.device_class.FORMATS)
             files = [f for f in files if f is not None]
             if not files:
                 dynamic.set('news_to_be_synced', set([]))