diff --git a/DFReader.py b/DFReader.py
index 6c268ffb16e15886441df5f997bd4e98068d4793..a19f0bb33dfff9b862e18ca9f25c4d7d1625fc9f 100644
--- a/DFReader.py
+++ b/DFReader.py
@@ -816,6 +816,7 @@ class DFReader_binary(DFReader):
                 if not idata in type_instances[mtype]:
                     # its a new one, need to parse it so we have the complete set of instances
                     type_instances[mtype].add(idata)
+                    self.offset = ofs
                     self._parse_next()
 
             self.counts[mtype] += 1