diff --git a/crazyflie/deps/crazyflie_tools b/crazyflie/deps/crazyflie_tools
index 36ea3d401..4b6255529 160000
--- a/crazyflie/deps/crazyflie_tools
+++ b/crazyflie/deps/crazyflie_tools
@@ -1 +1 @@
-Subproject commit 36ea3d40161db8f580dbb8846789bc036a2ccedd
+Subproject commit 4b6255529698e421f802b020eabeafd63b14be66
diff --git a/crazyflie/src/crazyflie_server.cpp b/crazyflie/src/crazyflie_server.cpp
index 4a71e0245..07734ed32 100644
--- a/crazyflie/src/crazyflie_server.cpp
+++ b/crazyflie/src/crazyflie_server.cpp
@@ -828,9 +828,11 @@ class CrazyflieROS
     }
 
     auto stats = cf_.connectionStatsDelta();
-    float ack_rate = stats.sent_count / stats.ack_count;
-    if (ack_rate < min_ack_rate_) {
-      RCLCPP_WARN(logger_, "Ack rate: %.1f %%", ack_rate * 100);
+    if (stats.ack_count > 0) {
+      float ack_rate = stats.sent_count / stats.ack_count;
+      if (ack_rate < min_ack_rate_) {
+        RCLCPP_WARN(logger_, "Ack rate: %.1f %%", name_.c_str(), ack_rate * 100);
+      }
     }
 
     if (publish_stats_) {