After reading all of the above and trying everything, we resigned ourselves to call out our trusty handyman. Even after cleaning out all the spray arms, we finally gave up after hours of tinkering. The pain was compounded by the fact that we had bought the machine 2nd hand only last week. This morning, we gave it one last go and after a jittery start followed by a thud, it seemed that the incoming water purged whatever it was blocking it and the machine sprung into action.