diff --git a/quic/quartc/quartc_session.cc b/quic/quartc/quartc_session.cc
index 38e1c62..79bc9bf 100644
--- a/quic/quartc/quartc_session.cc
+++ b/quic/quartc/quartc_session.cc
@@ -127,9 +127,12 @@
     return true;
   }
 
+  // Set transmission type to PROBING_RETRANSMISSION such that the packets will
+  // be padded to full.
   SetTransmissionType(PROBING_RETRANSMISSION);
+  // TODO(mellem): this sent PING will be retransmitted if it is lost which is
+  // not ideal. Consider to send stream data as probing data instead.
   SendPing();
-  WriteControlFrame(QuicFrame(QuicPaddingFrame()));
   return true;
 }