Removed the offending wheel centre caps. de-tarred and thoroughly cleaned the insides of the wheels and applied a coating of Bilt Hamber double speed wax. That's all the wax I have and I couldn't be ar$ed to walk to Halford's in the hope they had some dedicated wheel wax.
Also took the opportunity to wax the faces of the alloys and apply a coat of Megs Tyre Gel. Run out of that now so that's two items needed. Now back to OEM look in below photo.
Just about to put the Affalterbach caps in the classifieds if anyone is interested in buying them. If not its on to eBay.