We moved into a house last year that was cosmetically awful and spent the best part of the summer decorating. All of the woodwork in the house was done in a stone coloured satinwood, to match an MDF fire surround they had, and despite my great efforts I can't get it white. I sanded it (not to bare wood) and did 2 coats of undercoat and 2 coats of Dulux brilliant white gloss. Happy that I had an opaque white base I then used new tins of gloss and left 24 hours before the 2nd ( in some areas 3rd) coat. Now it all looks off white, as though the colour underneath is trying to come back. I have decorated all of my previous homes and never had this problem, any clues?