diff --git a/vtortola.WebSockets/Header/WebSocketFrameHeader.cs b/vtortola.WebSockets/Header/WebSocketFrameHeader.cs
index 1dab18ac..2e37c32f 100644
--- a/vtortola.WebSockets/Header/WebSocketFrameHeader.cs
+++ b/vtortola.WebSockets/Header/WebSocketFrameHeader.cs
@@ -106,14 +106,14 @@ public static Boolean TryParse(byte[] frameStart, int offset, int headerLength,
                 if (frameStart.Length < headerLength)
                     return false;
                 
-                contentLength = frameStart.ToUInt16(2, BitConverter.IsLittleEndian);
+                contentLength = frameStart.ToUInt16(offset+2, BitConverter.IsLittleEndian);
             }
             else if (contentLength == 127)
             {
                 if (frameStart.Length < headerLength)
                     return false;
 
-                var length = frameStart.ToUInt64(2, BitConverter.IsLittleEndian);
+                var length = frameStart.ToUInt64(offset+2, BitConverter.IsLittleEndian);
                 if (length > long.MaxValue)
                 {
                     throw new WebSocketException("The maximum supported frame length is 9223372036854775807, current frame is " + length.ToString());
diff --git a/vtortola.WebSockets/Rfc6455/WebSocketConnectionRfc6455.cs b/vtortola.WebSockets/Rfc6455/WebSocketConnectionRfc6455.cs
index 6c15936f..16525b17 100644
--- a/vtortola.WebSockets/Rfc6455/WebSocketConnectionRfc6455.cs
+++ b/vtortola.WebSockets/Rfc6455/WebSocketConnectionRfc6455.cs
@@ -248,19 +248,23 @@ private void ParseHeader(int readed)
 
         private async Task ParseHeaderAsync(int readed)
         {
-            if (await TryReadHeaderUntilAsync(readed, 6).ConfigureAwait(false) == -1)
+            var bytesRead = await TryReadHeaderUntilAsync(readed, 6).ConfigureAwait(false);
+            if (bytesRead == -1)
             {
                 Close(WebSocketCloseReasons.ProtocolError);
                 return;
             }
+            readed += bytesRead;
 
             var headerlength = WebSocketFrameHeader.GetHeaderLength(_headerBuffer.Array, _headerBuffer.Offset);
 
-            if (await TryReadHeaderUntilAsync(readed, headerlength).ConfigureAwait(false) == -1)
+            bytesRead = await TryReadHeaderUntilAsync(readed, headerlength).ConfigureAwait(false);
+            if (bytesRead == -1)
             {
                 Close(WebSocketCloseReasons.ProtocolError);
                 return;
             }
+            readed += bytesRead;
 
             await ProcessHeaderFrameAsync(headerlength).ConfigureAwait(false);
         }