diff --git a/audio/common/4.0/types.hal b/audio/common/4.0/types.hal
index d4c6efe..3675b7c 100644
--- a/audio/common/4.0/types.hal
+++ b/audio/common/4.0/types.hal
@@ -485,7 +485,7 @@
 };
 
 @export(name="", value_prefix="AUDIO_DEVICE_")
-enum AudioDevice : uint64_t {
+enum AudioDevice : uint32_t {
     NONE                          = 0x0,
     /** reserved bits */
     BIT_IN                        = 0x80000000,