I have an AEG 1030-W washing machine faulty spin cycle?

spins to 1000 rpm empty, as soon as any clothing is added to drum, spins up to about 300 rpm with violent motion then cuts out and returns to wash mode, then attempts to spin again again will only accelerate to about 300 rpm with violent motion and then fails and returns to wash mode.

Have had service man whos said it was faulty motor which when he returned was incorrect diagnosis. Then he said it was computer chip. He was most adament that it was not suspension but the machine sure behaves like it is out of balance. Machine checked for horisontal all OK.