diff --git a/lib/hci-socket/gatt.js b/lib/hci-socket/gatt.js
index 18dc52b..c5b2fe8 100644
--- a/lib/hci-socket/gatt.js
+++ b/lib/hci-socket/gatt.js
@@ -911,7 +911,9 @@ Gatt.prototype.handleWriteRequestOrCommand = function(request) {
               handleAttribute.emit('subscribe', this._mtu - 3, updateValueCallback);
             }
           } else {
-            handleAttribute.emit('unsubscribe');
+            if (handleAttribute.emit) {
+              handleAttribute.emit('unsubscribe');
+            }
           }
 
           result = ATT_ECODE_SUCCESS;