diff --git a/timm/bits/train_setup.py b/timm/bits/train_setup.py
index 5aca908f..87c1b5c5 100644
--- a/timm/bits/train_setup.py
+++ b/timm/bits/train_setup.py
@@ -72,9 +72,10 @@ def setup_model_and_optimizer(
                 'zero initialized BN layers (enabled by default for ResNets) while sync-bn enabled.')
 
     if isinstance(optimizer, Callable):
-        optimizer = optimizer(model=model, **optimizer_cfg)
+        # FIXME this interface needs to be figured out, model, model and/or parameters, or just parameters?
+        optimizer = optimizer(model, **optimizer_cfg)
     else:
-        optimizer = create_optimizer_v2(model=model, **optimizer_cfg)
+        optimizer = create_optimizer_v2(model, **optimizer_cfg)
 
     updater = create_updater(
         model=model,