X10 preset dimming problem

[lateralleap]

I'm using a Home Vision Pro to drive LD11
dimmers.

When trying to set dimmer to a specific
level, I find it sometimes works and
sometimes doesn't.

It is not a communications problem as On,
Off, Dim and Brighten commands always work.

Does anyone know which of the various Home
Vision "Set to Level" commands is the right
one for use with LD11 or anything else tha
might be causing this problem

Many thanks