Both of my dogs are incredibly sensitive. A few times I've been on the phone with my sister and my voice got kind of loud and both the dogs crawled slowly under the bed, tails tucked.

So I don't even raise my voice to them because I don't want to traumatize them and I know they would not respond to it. I taught them the leave it command which helps TREMENDOUSLY! They don't get into much trouble, but when they do, they're usually getting into something they need to leave alone - like the trash. I tell them to leave it, have them come to me and lay down, then they get a treat for being good. Positive reinforcement works wonders. Especially for my abused girl, Lolly, who is one of the most sensitive dogs I've ever encountered.