diff --git a/mammoth/tests/test_models.py b/mammoth/tests/test_models.py
index 089ca796..aea9355f 100644
--- a/mammoth/tests/test_models.py
+++ b/mammoth/tests/test_models.py
@@ -14,7 +14,7 @@
 mammoth.opts._add_train_general_opts(parser)
 
 # -data option is required, but not used in this test, so dummy.
-opts = parser.parse_known_args(['-tasks', 'dummy', '-node_rank', '0', '-model_dim', '500'])[0]
+opts = parser.parse_known_args(['-tasks', 'dummy', '-node_rank', '0', '-model_dim', '500'], strict=False)[0]
 
 
 class TestModel(unittest.TestCase):
diff --git a/mammoth/utils/parse.py b/mammoth/utils/parse.py
index 54a485c3..79a000f7 100644
--- a/mammoth/utils/parse.py
+++ b/mammoth/utils/parse.py
@@ -269,9 +269,9 @@ def defaults(cls, *args):
         defaults = dummy_parser.parse_known_args([])[0]
         return defaults
 
-    def parse_known_args(self):
-        opts, unknown = super().parse_known_args()
-        if unknown:
+    def parse_known_args(self, *args, strict=True, **kwargs):
+        opts, unknown = super().parse_known_args(*args, **kwargs)
+        if strict and unknown:
             raise ValueError(f'unknown arguments provided:\n{unknown}')
         return opts, unknown