Failed communication with most people

It's a fact. I have heard this since I was a kid. The first recollection that made a huge impact on me was from a much older sister at church whom i admire for her talents and wits. She wrote me a note saying that one of my greatest weakness is that I come across most of the time as arrogant and difficult. I read it, locked it in my private "drawer -of-everything-important" and took it out to read ever so often.

Communication is not my strength (ironic for the fact that I am an interpreter by profession and linguistics is part of my post graduate pursuit). Guess all the knowledge in the world does not help one to comunciate better.

I consciously make the effort to express things as plain as possible. The response I get: Sam you make things complicated. When I try to ask for clarifcations, people think I am challening them with rhetorics. I tried my best to ask in the least intimidating manner possible. But I failed, time and again...