diff --git a/ngclearn/components/synapses/modulated/MSTDPETSynapse.py b/ngclearn/components/synapses/modulated/MSTDPETSynapse.py
index 65c1ebd0a..c22eabcad 100755
--- a/ngclearn/components/synapses/modulated/MSTDPETSynapse.py
+++ b/ngclearn/components/synapses/modulated/MSTDPETSynapse.py
@@ -79,7 +79,7 @@ def __init__(self, name, shape, A_plus, A_minus, eta=1., mu=0.,
         self.elg_decay = elg_decay
         ## MSTDP/MSTDP-ET compartments
         self.modulator = Compartment(jnp.zeros((self.batch_size, 1)))
-        self.output_mask = Compartment(jnp.ones((self.batch_size, self.weights.shape[1])))
+        self.output_mask = Compartment(jnp.ones((self.batch_size, self.weights.value.shape[1])))
         self.eligibility = Compartment(jnp.zeros(shape))
 
     @staticmethod