diff --git a/py34/bacpypes/bvllservice.py b/py34/bacpypes/bvllservice.py
index b81f4eb..7e93716 100755
--- a/py34/bacpypes/bvllservice.py
+++ b/py34/bacpypes/bvllservice.py
@@ -141,7 +141,7 @@ class UDPMultiplexer:
             return
 
         # extract the first octet
-        msg_type = struct.unpack('b', pdu.pduData[:1])[0]
+        msg_type = (pdu.pduData)[0]
 
         # check for the message type
         if msg_type == 0x01: