diff --git a/fastkml/base.py b/fastkml/base.py
index 64e78887..197f4a98 100644
--- a/fastkml/base.py
+++ b/fastkml/base.py
@@ -143,6 +143,8 @@ def _get_kwargs(
         strict: bool,
     ) -> Dict[str, Any]:
         """Returns a dictionary of kwargs for the class constructor."""
+        name_spaces = name_spaces or {}
+        name_spaces = {**config.NAME_SPACES, **name_spaces}
         kwargs: Dict[str, Any] = {"ns": ns, "name_spaces": name_spaces}
         return kwargs
 
diff --git a/fastkml/gx.py b/fastkml/gx.py
index 5a81c8b7..b40a07b4 100644
--- a/fastkml/gx.py
+++ b/fastkml/gx.py
@@ -448,7 +448,7 @@ def _get_kwargs(
             strict=strict,
         )
         kwargs["tracks"] = cls._get_track_kwargs_from_element(
-            ns=config.GXNS,
+            ns=kwargs["name_spaces"].get("gx", ""),
             element=element,
             strict=strict,
         )