First thing I would do is check all of your connections, especially the grounds. Static is an issue but something like this is usually a grounding/connection issue - noise from the motor is harming the USB connection.
The second thing I would do is get a ground/neutral checked and check your outlets - are they really grounded properly?
@WillAdams and others can point to some SO3 specific articles. I see you’ve had your machine for a while. There is an add a capacitor fix that dramatically helps many with older hardware (the latest stuff has it built in).
This was written about the Nomad but is useful in the general case of power and ground issues:
Separating and isolating your SO3, vac, and computer is really a good idea - different circuit breakers, if possible. Using a quality UPS - not surge protector - can really help.
A dust shoe will reduce static but this is often minor. Without a dust shoe and enclosure you’re exposing yourself to dangers if your working in friable materials (e.g. wood, MDF, Garolite, FR4, Fiberglass, carbon composite). Consider a vacuum system and enclosure: