Looks like the Breville FP is a direct drive induction motor machine. Fractional horsepower induction motors are the simplest mechanical electrical devices with only one moving part, i.e. the rotor. The rotor is typically dynamically balanced. They tend to run very silent.
However, higher horsepower induction motors can be a little more complicated. They incorporate additional components to reduce power draw when starting. For instance, they can have switches controlled by centrifugal weights to turn on and off. Those can make noise when the motor starts and stops.
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