diff --git a/packages/SystemUI/src/com/android/systemui/volume/VolumeDialogControllerImpl.java b/packages/SystemUI/src/com/android/systemui/volume/VolumeDialogControllerImpl.java
index f19c49cc123f3..699c1393da049 100644
--- a/packages/SystemUI/src/com/android/systemui/volume/VolumeDialogControllerImpl.java
+++ b/packages/SystemUI/src/com/android/systemui/volume/VolumeDialogControllerImpl.java
@@ -75,6 +75,7 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Optional;
+import java.util.concurrent.ConcurrentHashMap;
 
 import javax.inject.Inject;
 import javax.inject.Singleton;
@@ -829,7 +830,7 @@ public class VolumeDialogControllerImpl implements VolumeDialogController, Dumpa
     }
 
     class C implements Callbacks {
-        private final HashMap<Callbacks, Handler> mCallbackMap = new HashMap<>();
+        private final Map<Callbacks, Handler> mCallbackMap = new ConcurrentHashMap<>();
 
         public void add(Callbacks callback, Handler handler) {
             if (callback == null || handler == null) throw new IllegalArgumentException();