diff --git a/edosl0util/stream.py b/edosl0util/stream.py
index f06ac8491dfa52e0b46581bdda164922c61d2f07..2c7c075ed6b6ea949e0ff0b9223a08991fc54312 100644
--- a/edosl0util/stream.py
+++ b/edosl0util/stream.py
@@ -31,10 +31,9 @@ class PacketTooShort(Error):
     After this error occurs the stream is no longer usable because data offsets
     are no longer reliable.
     """
-    def __init__(self, header=None, offset=None):
-        self.offset = offset
+    def __init__(self, header=None):
         self.primary_header = header
-        self.args = (self.offset, self.primary_header)
+        self.args = (self.primary_header,)
 
 
 class NonConsecutiveSeqId(Error):
@@ -49,7 +48,6 @@ class SimpleStream(object):
     """
     def __init__(self, fobj):
         self.fobj = fobj
-        self.offset = fobj.tell()
 
     def __iter__(self):
         return self
@@ -63,14 +61,13 @@ class SimpleStream(object):
         if not buf:
             raise StopIteration()
         if len(buf) < psize:
-            raise PacketTooShort(header=None, offset=self.offset)
+            raise PacketTooShort(header=None)
         h1 = PrimaryHeader.from_buffer_copy(buf)
         # read user data
         size = h1.data_length_minus1 + 1
         buf = self.fobj.read(size)
         if len(buf) < size:
-            raise PacketTooShort(header=h1, offset=self.offset)
-        self.offset += (psize + size)
+            raise PacketTooShort(header=h1)
         return h1, buf