I sold our first ISE10 this week and delivered and installed it today, I was impressed with the build quality of the appliance but was surprised at the amount of noise on spin mainly from the motor, much more noise than the ISE 5 Mk 1 & II.
I would have expected the machine to be more refined on noise level and whilst the appliance was on spin I was aware that both the customers voice and mine was raised !
I posted on this issue when I sold my first ISE10 and had a similar experience. It was a knocking noise and meant the spin was quite noisy compared to the ISE 5 /2 induction motor.
It turned out to be the belt, sat in one position on the motor pulley while in storage and transit. It knocked quite loudly for the first 10 minutes.
To avoid any embarrassment, I now run each machine for 2 spin cycles prior to delivery. That seems enough to settle the belt and the knocking subsides.