Merge "res/res_rtp_asterisk: remove debug traces generated by an empty frame" into 13

res/res_rtp_asterisk.c

@@ -6058,7 +6058,9 @@ static int red_write(const void *data)
 	struct ast_rtp *rtp = ast_rtp_instance_get_data(instance);
 
 	ao2_lock(instance);
-	ast_rtp_write(instance, &rtp->red->t140);
+	if (rtp->red->t140.datalen > 0) {
+		ast_rtp_write(instance, &rtp->red->t140);
+	}
 	ao2_unlock(instance);
 
 	return 1;