diff --git a/src/gluonts/model/deepstate/issm.py b/src/gluonts/model/deepstate/issm.py
index 8135e365b3..f7c967920f 100644
--- a/src/gluonts/model/deepstate/issm.py
+++ b/src/gluonts/model/deepstate/issm.py
@@ -201,8 +201,7 @@ def transition_coeff(
         F = getF(seasonal_indicators)
 
         _transition_coeff = (
-            # TODO: this won't work if F == mx.sym
-            F.array([[1, 1], [0, 1]])
+            (F.diag(F.ones(shape=(2,)), k=0) + F.diag(F.ones(shape=(1,)), k=1))
             .expand_dims(axis=0)
             .expand_dims(axis=0)
         )
diff --git a/test/model/test_deepstate_smoke.py b/test/model/test_deepstate_smoke.py
index 1f5b09adf5..4e25b5859a 100644
--- a/test/model/test_deepstate_smoke.py
+++ b/test/model/test_deepstate_smoke.py
@@ -26,8 +26,11 @@
 common_estimator_hps = dict(
     freq="D",
     prediction_length=3,
-    trainer=Trainer(epochs=3, num_batches_per_epoch=2, batch_size=1),
+    trainer=Trainer(
+        epochs=3, num_batches_per_epoch=2, batch_size=1, hybridize=True
+    ),
     past_length=10,
+    add_trend=True,
 )