diff --git a/src/switch_rtp.c b/src/switch_rtp.c
index e2fcf45419..199c9e95f7 100644
--- a/src/switch_rtp.c
+++ b/src/switch_rtp.c
@@ -8503,7 +8503,7 @@ static int rtp_common_write(switch_rtp_t *rtp_session,
 	}
 
 	if (switch_rtp_test_flag(rtp_session, SWITCH_RTP_FLAG_VIDEO)) {
-		int external = (*flags & SFF_EXTERNAL);
+		int external = (flags && *flags & SFF_EXTERNAL);
 		/* Normalize the timestamps to our own base by generating a made up starting point then adding the measured deltas to that base
 		   so if the timestamps and ssrc of the source change, it will not break the other end's jitter bufffer / decoder etc *cough* CHROME *cough*
 		 */