Well, it's taken me a couple of years, but I finally applied a tip I read in a novel. I stuck self-adhesive foam tape to the head of the vacuum cleaner and voila! No more banging and scratching furniture. Who says novel-reading isn't practical? :)
The tip came from Trisha Ashley's A Winter's Tale. I really enjoy her cosy ironic romances. My favourite is The Urge to Jump.