diff --git a/acme/agents/jax/dqn/config.py b/acme/agents/jax/dqn/config.py
index 3200f02367..2ec19f56c8 100644
--- a/acme/agents/jax/dqn/config.py
+++ b/acme/agents/jax/dqn/config.py
@@ -79,8 +79,9 @@ class DQNConfig:
   num_sgd_steps_per_step: int = 1
 
 
-def logspace_epsilons(num_epsilons: int, epsilon: float = 0.017
-                      ) -> Sequence[float]:
+def logspace_epsilons(
+    num_epsilons: int, epsilon: float = 0.017
+) -> Union[Sequence[float], jnp.ndarray]:
   """`num_epsilons` of logspace-distributed values, with median `epsilon`."""
   if num_epsilons <= 1:
     return (epsilon,)
diff --git a/acme/agents/jax/r2d2/learning.py b/acme/agents/jax/r2d2/learning.py
index 8ac7b475ab..f974d76b01 100644
--- a/acme/agents/jax/r2d2/learning.py
+++ b/acme/agents/jax/r2d2/learning.py
@@ -78,8 +78,8 @@ def loss(
         params: networks_lib.Params,
         target_params: networks_lib.Params,
         key_grad: networks_lib.PRNGKey,
-        sample: reverb.ReplaySample
-    ) -> Tuple[jnp.ndarray, Tuple[jnp.ndarray, jnp.ndarray]]:
+        sample: reverb.ReplaySample,
+    ) -> Tuple[jnp.ndarray, jnp.ndarray]:
       """Computes mean transformed N-step loss for a batch of sequences."""
 
       # Get core state & warm it up on observations for a burn-in period.
diff --git a/acme/jax/losses/mpo.py b/acme/jax/losses/mpo.py
index 6902c00cf2..d2958f75a6 100644
--- a/acme/jax/losses/mpo.py
+++ b/acme/jax/losses/mpo.py
@@ -50,24 +50,24 @@ class MPOParams(NamedTuple):
 
 class MPOStats(NamedTuple):
   """NamedTuple to store loss statistics."""
-  dual_alpha_mean: float
-  dual_alpha_stddev: float
-  dual_temperature: float
+  dual_alpha_mean: Union[float, jnp.ndarray]
+  dual_alpha_stddev: Union[float, jnp.ndarray]
+  dual_temperature: Union[float, jnp.ndarray]
 
-  loss_policy: float
-  loss_alpha: float
-  loss_temperature: float
-  kl_q_rel: float
+  loss_policy: Union[float, jnp.ndarray]
+  loss_alpha: Union[float, jnp.ndarray]
+  loss_temperature: Union[float, jnp.ndarray]
+  kl_q_rel: Union[float, jnp.ndarray]
 
-  kl_mean_rel: float
-  kl_stddev_rel: float
+  kl_mean_rel: Union[float, jnp.ndarray]
+  kl_stddev_rel: Union[float, jnp.ndarray]
 
-  q_min: float
-  q_max: float
+  q_min: Union[float, jnp.ndarray]
+  q_max: Union[float, jnp.ndarray]
 
-  pi_stddev_min: float
-  pi_stddev_max: float
-  pi_stddev_cond: float
+  pi_stddev_min: Union[float, jnp.ndarray]
+  pi_stddev_max: Union[float, jnp.ndarray]
+  pi_stddev_cond: Union[float, jnp.ndarray]
 
   penalty_kl_q_rel: Optional[float] = None
 
diff --git a/acme/jax/networks/atari.py b/acme/jax/networks/atari.py
index 37ca991879..7df76fbf3f 100644
--- a/acme/jax/networks/atari.py
+++ b/acme/jax/networks/atari.py
@@ -22,7 +22,7 @@
 - X?: X is optional (e.g. optional batch/sequence dimension).
 
 """
-from typing import Optional, Tuple, Sequence
+from typing import Any, Optional, Sequence, Tuple
 
 from acme.jax.networks import base
 from acme.jax.networks import duelling
@@ -120,9 +120,9 @@ def __init__(self, num_actions: int):
     self._head = policy_value.PolicyValueHead(num_actions)
     self._num_actions = num_actions
 
-  def __call__(self, inputs: observation_action_reward.OAR,
-               state: hk.LSTMState) -> base.LSTMOutputs:
-
+  def __call__(
+      self, inputs: observation_action_reward.OAR, state: hk.LSTMState
+  ) -> Any:
     embeddings = self._embed(inputs)  # [B?, D+A+1]
     embeddings, new_state = self._core(embeddings, state)
     logits, value = self._head(embeddings)  # logits: [B?, A], value: [B?, 1]
@@ -133,8 +133,9 @@ def initial_state(self, batch_size: Optional[int],
                     **unused_kwargs) -> hk.LSTMState:
     return self._core.initial_state(batch_size)
 
-  def unroll(self, inputs: observation_action_reward.OAR,
-             state: hk.LSTMState) -> base.LSTMOutputs:
+  def unroll(
+      self, inputs: observation_action_reward.OAR, state: hk.LSTMState
+  ) -> Any:
     """Efficient unroll that applies embeddings, MLP, & convnet in one pass."""
     embeddings = self._embed(inputs)
     embeddings, new_states = hk.static_unroll(self._core, embeddings, state)