diff --git a/ophyd_devices/sim/sim_monitor.py b/ophyd_devices/sim/sim_monitor.py
index 8326403..f26c5bc 100644
--- a/ophyd_devices/sim/sim_monitor.py
+++ b/ophyd_devices/sim/sim_monitor.py
@@ -83,6 +83,7 @@ class SimMonitorAsyncPrepare(CustomDetectorMixin):
         self._random_send_interval = None
         self._counter = 0
         self.prep_random_interval()
+        self.parent.current_trigger.subscribe(self._progress_update, run=False)
 
     def clear_buffer(self):
         """Clear the data buffer."""
@@ -99,7 +100,6 @@ class SimMonitorAsyncPrepare(CustomDetectorMixin):
         """Prepare the device for staging."""
         self.clear_buffer()
         self.prep_random_interval()
-        self.parent.current_trigger.subscribe(self._progress_update, run=False)
 
     def on_complete(self):
         """Prepare the device for completion."""
@@ -135,7 +135,7 @@ class SimMonitorAsyncPrepare(CustomDetectorMixin):
         if self._counter % self._random_send_interval == 0:
             self._send_data_to_bec()
 
-    def _progress_update(self, value: int):
+    def _progress_update(self, value: int, **kwargs):
         """Update the progress of the device."""
         max_value = self.parent.scaninfo.num_points
         self.parent._run_subs(
diff --git a/ophyd_devices/sim/sim_signals.py b/ophyd_devices/sim/sim_signals.py
index 7364173..554ff2b 100644
--- a/ophyd_devices/sim/sim_signals.py
+++ b/ophyd_devices/sim/sim_signals.py
@@ -34,6 +34,8 @@ class SetableSignal(Signal):
     precision (float)        : Precision of the signal, default PRECISION.
     """
 
+    SUB_VALUE = "value"
+
     def __init__(
         self,
         name: str,
@@ -84,6 +86,7 @@ class SetableSignal(Signal):
         """
         self._update_sim_state(value)
         self._value = value
+        self._run_subs(sub_type=self.SUB_VALUE, value=value)
 
     def describe(self):
         """Describe the readback signal.