diff --git a/radicale/app/__init__.py b/radicale/app/__init__.py
index 271528fb..e52934dd 100644
--- a/radicale/app/__init__.py
+++ b/radicale/app/__init__.py
@@ -309,12 +309,13 @@ class Application(ApplicationPartDelete, ApplicationPartHead,
                 flags_text = ""
             # delay on error
             if status >= 400:
-                random_delay = self._delay_on_error * (1 + random.random())
-                if status >= 500:
-                    random_delay = 2 * random_delay
-                if logger.isEnabledFor(logging.DEBUG):
-                    logger.debug("Response delay triggered by result code: %d -> %0.3f seconds", status, random_delay)
-                time.sleep(random_delay)
+                if self._delay_on_error > 0:
+                    random_delay = self._delay_on_error * (1 + random.random())
+                    if status >= 500:
+                        random_delay = 2 * random_delay
+                    if logger.isEnabledFor(logging.DEBUG):
+                        logger.debug("Response delay triggered by result code: %d -> %0.3f seconds", status, random_delay)
+                    time.sleep(random_delay)
             if answer is not None:
                 logger.info("%s response status for %r%s in %.3f seconds %s %s bytes%s: %s",
                             request_method, unsafe_path, depthinfo,