diff --git a/blackjax/adaptation/mclmc_adaptation.py b/blackjax/adaptation/mclmc_adaptation.py
index 1846eb1b3..b19bad9ff 100644
--- a/blackjax/adaptation/mclmc_adaptation.py
+++ b/blackjax/adaptation/mclmc_adaptation.py
@@ -166,8 +166,7 @@ def L_step_size_adaptation(state, params, num_steps, rng_key):
         num_steps1, num_steps2 = int(num_steps * frac_tune1), int(
             num_steps * frac_tune2
         )
-        # L_step_size_adaptation_keys = jax.random.split(rng_key, num_steps1 + num_steps2)
-        L_step_size_adaptation_keys = jnp.array([rng_key] * (num_steps1 + num_steps2))
+        L_step_size_adaptation_keys = jax.random.split(rng_key, num_steps1 + num_steps2)
 
         # we use the last num_steps2 to compute the diagonal preconditioner
         outer_weights = jnp.concatenate((jnp.zeros(num_steps1), jnp.ones(num_steps2)))
@@ -201,8 +200,7 @@ def make_adaptation_L(kernel, frac, Lfactor):
 
     def adaptation_L(state, params, num_steps, key):
         num_steps = int(num_steps * frac)
-        # adaptation_L_keys = jax.random.split(key, num_steps)
-        adaptation_L_keys = jnp.array([key] * (num_steps))
+        adaptation_L_keys = jax.random.split(key, num_steps)
 
         # run kernel in the normal way
         state, info = jax.lax.scan(