diff --git a/tests/contrib/collection.py b/tests/contrib/collection.py
index cfb473a..0aa7f90 100644
--- a/tests/contrib/collection.py
+++ b/tests/contrib/collection.py
@@ -575,7 +575,7 @@ def test_ttl_of_stored_collection_should_be_set(self):
         # test expire
         stored_collection = collection.store(ttl=1)
         self.assertTrue(0 <= self.connection.ttl(stored_collection.stored_key) <= 1)
-        time.sleep(1)
+        time.sleep(1.1)
         self.assertFalse(self.connection.exists(stored_collection.stored_key))
 
     def test_stored_key_should_be_the_given_one_if_set(self):
@@ -590,7 +590,7 @@ def test_stored_collection_should_raise_if_key_expired(self):
 
         # try with short ttl
         stored_collection = collection.store(ttl=1)
-        time.sleep(1)
+        time.sleep(1.1)
         with self.assertRaises(DoesNotExist):
             list(stored_collection)