Vibration problem, new machine, help!?

I just bought an Indesit WIA121, 1200 spin. Its fairly quiet except for when its in the spin cycle. It vibrates so excessively that I can feel the floor and wall move in the bathroom next door. I've checked front castors, and balanced it. It doesnt vibrate when its spinning on empty.Its in a fitted kitchen unit with about 5 inches space from the wall, and an inch on each side. Washing machine doesnt move around, just vibrates badly. Any suggestions? Or modifications to absorb vibration? I'm in a flat and want to minimise noise for elderly neighbour downstairs also! Thanks.