diff --git a/frappy_psi/ls372.py b/frappy_psi/ls372.py
index 847cf2a7..9ce8e34b 100644
--- a/frappy_psi/ls372.py
+++ b/frappy_psi/ls372.py
@@ -196,7 +196,7 @@ class ResChannel(Channel):
     enabled = Parameter('is this channel enabled?', datatype=BoolType(), readonly=False)
     pause = Parameter('pause after channel change', datatype=FloatRange(3, 60, unit='s'), readonly=False)
     dwell = Parameter('dwell time with autoscan', datatype=FloatRange(1, 200, unit='s'), readonly=False)
-    filter = Parameter('filter time', datatype=FloatRange(0, 200, unit='s'), readonly=False)
+    filter = Parameter('filter time', datatype=FloatRange(1, 200, unit='s'), readonly=False)
 
     _toggle_autorange = 'init'
     _prev_rdgrng = (1, 1)  # last read values for icur and exc
@@ -216,7 +216,7 @@ class ResChannel(Channel):
     def change(self, command, *args):
         cmd, _, qarg = command.partition(' ')
         args = ','.join([qarg] + [f'{a:g}' for a in args])
-        return parse(self.switcher.communicate(f'{cmd} {args};{cmd}?{qarg}'))
+        return parse(self.switcher.communicate(f'{command} {args};{command}?{qarg}'))
 
     def read_status(self):
         if not self.enabled: