[gumbysuz]

I have learned that Dori will look to me for my reaction if anything out of the ordinary happens. I just say, "you're ok" and go about my business.
For desensitizing, I use the "check it out" command. This means get as close as she can to the object and get a treat. Objective is to eventually touch it with her nose. We have used this method on vacuum cleaners, plastic bags, fireplace, garbage cans, new objects brought into the house, canes, bicycle wheels, etc.
Noises are a different issue. Usually "you're ok" and my calm demeanor seem to work.
Again, consistency and practice.