diff --git a/roombapy/roomba.py b/roombapy/roomba.py
index d6af564..0064462 100755
--- a/roombapy/roomba.py
+++ b/roombapy/roomba.py
@@ -221,7 +221,9 @@ def send_command(self, command, params=None):
         }
         roomba_command.update(params)
 
-        str_command = orjson.dumps(roomba_command).decode("utf-8")
+        # params may contain non-string keys, so we need to use the orjson
+        # OPT_NON_STR_KEYS option
+        str_command = orjson.dumps(roomba_command, option=orjson.OPT_NON_STR_KEYS).decode("utf-8")
         self.log.debug("Publishing Roomba Command : %s", str_command)
         self.remote_client.publish("cmd", str_command)