diff --git a/rpyc/core/protocol.py b/rpyc/core/protocol.py
index bd8b7b8a..f54825ca 100644
--- a/rpyc/core/protocol.py
+++ b/rpyc/core/protocol.py
@@ -293,7 +293,7 @@ def _unbox(self, package):  # boxing
         if label == consts.LABEL_LOCAL_REF:
             return self._local_objects[value]
         if label == consts.LABEL_REMOTE_REF:
-            id_pack = value  # so value is a id_pack
+            id_pack = (str(value[0]), value[1], value[2])  # so value is a id_pack
             if id_pack in self._proxy_cache:
                 proxy = self._proxy_cache[id_pack]
                 proxy.____refcount__ += 1  # if cached then remote incremented refcount, so sync refcount