Cleaning, polishing Speaker Cabinets ?

Novus plastic cleaner (comes in 3 intensities for various scratch removal needs) is what pro guitar repair people (Pat DiBurro who is a guitar repair genius and an official repair dude for Martin, Taylor and others, turned me on to this stuff after noting that guitar makers like Collings use it). I use the lightest version to clean my motorcycle helmet shield so that stuff is VERY light, and nothing short of amazing. Poly finishes and nitrocellulose finishes differ, but Novus seems to work on anything. Pledge, amazingly, is also useful on lots of woods, and my speakers are covered with vinyl fake wood so anything works...hose 'em off outside, wipe 'em with a sleeping cat, put on a bunny suit and wrestle 'em...

Cinch, made by Spic and Span. Does not leave a residue at all. I know several audiophiles and dealers who use it on gear, whether it's plastic , finished wood, metal, granite, etc. Great on windows too! Use it sparingly on soft cloth and clean way. Again, NO RESIDUE.