Recently my washing machine started acting up, on some of the programmes the dial sticks and you have to manually move the dial. The water heats up the same as always but the programme only unsticks if you add a limescale remover block to the wash cycle, but the moment you wash without a limescale remover block the programmes start to stick again,on average it takes my washing machine up to 5hrs to complete its cycle. I cannot keep adding limescale remover blocks to the wash cycle as this is very expensive. Do i need a new washing machine?