Have you had a look inside the washing machine to see if you can see any rust in there? otherwise it might be coming from the water pipes itself, so replacing the machine wont help. If you cant see any rust in the machine, take hose off and run it into the laundry sink (or white container) and see if the water is discoloured, maybe let it sit for a little bit to see if the rust settles on the bottom.

If the rust is inside you might be able to get appliance paint from hervey norman to cover the chip. GL