diff --git a/xxHashSharp/xxHash.cs b/xxHashSharp/xxHash.cs
index c47e366..543ebf9 100644
--- a/xxHashSharp/xxHash.cs
+++ b/xxHashSharp/xxHash.cs
@@ -240,7 +240,7 @@ public bool Update(byte[] input, int len)
                 _state.v4 = CalcSubHash(_state.v4, _state.memory, index);
                 index += 4;
 
-                index = 0;
+                index = 16 - _state.memsize;
                 _state.memsize = 0;
             }