Than take them of and dipp them in Domestos solution (dilute Domestos with water)in a jar and leave them a day or two. Domestos clears everything. I‘ve used it o yellowed plastic, metal even ceramics.MyOhMy said:Hi, LJV. The slider controls have, sadly yellowed with age - but it's not the end of the world!
Rinse and scrubb. Keep children and pets from the Domestos and wear protective glowes.
It does wonders. You can test it first on some junk piece of aged/yellowed plastic.