diff --git a/src/ConnectionTester.c b/src/ConnectionTester.c
index c5fd58e..78f9382 100644
--- a/src/ConnectionTester.c
+++ b/src/ConnectionTester.c
@@ -19,7 +19,8 @@ unsigned int LiGetPortFlagsFromStage(int stage)
     switch (stage)
     {
         case STAGE_RTSP_HANDSHAKE:
-            return ML_PORT_FLAG_TCP_48010 | ML_PORT_FLAG_UDP_48010;
+            // GFE 3.22 requires a successful ping on 48000 to complete RTSP handshake
+            return ML_PORT_FLAG_TCP_48010 | ML_PORT_FLAG_UDP_48010 | ML_PORT_FLAG_UDP_48000;
 
         case STAGE_CONTROL_STREAM_START:
             return ML_PORT_FLAG_UDP_47999;