diff --git a/CHANGES.md b/CHANGES.md
index 179e25f..4faf3ef 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,6 +1,7 @@
 ## 0.13.1-SNAPSHOT
 
 * Remove any? in com.rpl.specter.impl to avoid conflict with Clojure 1.9
+* Bug fix: Fix regression from 0.13.0 where [ALL FIRST] on a PersistentArrayMap that created duplicate keys would create an invalid PersistentArrayMap
 
 ## 0.13.0
 
diff --git a/src/clj/com/rpl/specter/navs.cljc b/src/clj/com/rpl/specter/navs.cljc
index a613ed5..a5ce306 100644
--- a/src/clj/com/rpl/specter/navs.cljc
+++ b/src/clj/com/rpl/specter/navs.cljc
@@ -108,7 +108,7 @@
                (aset array i newk)
                (aset array (inc i) newv)
                (recur (+ i 2)))))
-         (clojure.lang.PersistentArrayMap. array))))
+         (clojure.lang.PersistentArrayMap/createAsIfByAssoc array))))
 
 
   #?(:cljs cljs.core/PersistentArrayMap)
diff --git a/test/com/rpl/specter/core_test.cljc b/test/com/rpl/specter/core_test.cljc
index 1486a9a..2e23cc5 100644
--- a/test/com/rpl/specter/core_test.cljc
+++ b/test/com/rpl/specter/core_test.cljc
@@ -1297,3 +1297,8 @@
     (is (= s/NONE (afn :c :a)))
     (is (= data (afn :b :a)))
     (is (= data (afn :b :b)))))
+
+(deftest duplicate-map-keys-test
+  (let [res (setval [s/ALL s/FIRST] "a" {:a 1 :b 2})]
+    (is (= {"a" 2} res))
+    (is (= 1 (count res)))))