It's plastic. I was reading here further and apparently the XPS3's can have the same problems. Is the XP XPNR a possible solution? It says it filters noise.
Manowar,
After you mentioned the posts regarding the XPS3's I searched myself - yep, you're correct. What's worse is I was involved in a couple of those threads and completely forgot about it (the mind is the first this to ...).
Anyway, I said it back in '07 and I'll repeat it now - a relay switch should not have this problem. I can see absolutely no go reason for having a load sense circuit on the output of a relay wall switch. Still, we have the obvious reports of problems. I can't argue with these facts. There appears to be something in the "newer" XPS3's that allows them to be fooled into turning back on when used with some fans (at some speeds).
From now on I'll stop suggesting what should work and rely on what I have recent first hand experience with -
I am using Smarthome Icon and Switchlinc relay switches on both Hunter and Harbor Breeze fans. I have had zero problems with any of these (5) fans at any speed.
I've used the Inlinelinc relay module at a friends installation (2 fans - don't know the make).
Sorry if I lead you down a path...
Boiler