Non-contact voltage testers are notorious for beeping in response to static. Mine will beep on dead wires if I move it around a lot or drag it up and down the insulation or even the wallboard.
Test with a real multimeter between the handle/frame and a known good ground (the ground pin of a nearby outlet will work fine). You should see 0VAC (or more likely, a minuscule amount of volts AC quickly dropping to 0 as static dissipates).
If you see a voltage that stays above zero, you can be worried and keep searching for an issue with your appliance. If the number is zero, you are fine - the non-contact detector is just beeping at static.