diff --git a/Assets/FishNet/Runtime/Managing/Timing/TimeManager.cs b/Assets/FishNet/Runtime/Managing/Timing/TimeManager.cs
index 685178b7..0073aa5f 100644
--- a/Assets/FishNet/Runtime/Managing/Timing/TimeManager.cs
+++ b/Assets/FishNet/Runtime/Managing/Timing/TimeManager.cs
@@ -1242,6 +1242,12 @@ public void SetTickRate(ushort value)
         #region UNITY_EDITOR
         private void OnValidate()
         {
+            /* Physics mode sets Physics.simulationMode and Time.fixedDeltaTime, which
+             * outside play mode are the project settings: they would be saved with the
+             * project and baked into player builds. */
+            if (!Application.isPlaying)
+                return;
+
             SetInitialValues();
         }
         #endregion