how do i stop machine shaking violently and very loud on spinning?

i have a whirlpool sixth sense washing machine which when on spins shakes violently(husband has tried wedging wood down side but to no avail) the machine has been levelled as best can be but still makes no difference. also when spinning it is so loud our neighbour can hear when they are in their living room which is a house width away!!! other than this it cleans perfectly, any one have any ideas much appreciated.