diff --git a/lisainstrument/instrument.py b/lisainstrument/instrument.py
index f208a38d3ad30d5d78410bc75effd0f8e6c8308f..8328c71895812d5dbba08300db6cef0cbeb3ba17 100755
--- a/lisainstrument/instrument.py
+++ b/lisainstrument/instrument.py
@@ -824,9 +824,11 @@ class Instrument:
 
         Args:
             but: optional category of noises to keep on ['laser', 'modulation',
-                'clock', 'pathlength', 'ranging', 'jitters']
+                'clock', 'pathlength', 'ranging', 'jitters', 'dws', 'sync']
         """
-        valid_noises = ['laser', 'modulation', 'clock', 'pathlength', 'ranging', 'jitters']
+        valid_noises = [
+            'laser', 'modulation', 'clock', 'pathlength',
+            'ranging', 'jitters', 'dws', 'sync']
         if but is not None and but not in valid_noises:
             raise ValueError(f"unknown noise '{but}'")
 
@@ -842,6 +844,10 @@ class Instrument:
             self.disable_ranging_noises()
         if but != 'jitters':
             self.disable_jitters()
+        if but != 'dws':
+            self.dws_asds = ForEachMOSA(0)
+        if but != 'sync':
+            self.sync_asds = ForEachSC(0)
 
     def disable_clock_noises(self):
         """Turn off all imperfections on clocks.