diff --git a/bin/check.sh b/bin/check.sh
index b3f3e754..5ac19836 100755
--- a/bin/check.sh
+++ b/bin/check.sh
@@ -252,6 +252,7 @@ function run_sipp
       echo "$(date) - $base error"
       status=1
     fi
+    sleep 1
   done
 
   for res in ${responder_pid}; do