Never WD40 as you know and really not even silicon grease on the mast, just a good strong upwards clean with an alcohol based tissue and then throughly dried off with a clean tissue until spotless and dry.
If it's still sticking and making a ratcheting noise then instal a new mast and perlon.
I'm pretty sure I've got a brand new boxed one kicking around in the garage, I can bring it along on the Tour if want Martin??